Androstanolone, or stanolone, also known as dihydrotestosterone (DHT) and sold under the brand name Andractim among others, is an

androgen An androgen (from Greek ''andr-'', the stem of the word meaning ) is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes ...

and

anabolic steroid Anabolic steroids, also known as anabolic-androgenic steroids (AAS), are a class of drugs that are structurally related to testosterone, the main male sex hormone, and produce effects by binding to the androgen receptor (AR). Anabolism, Anaboli ...

(AAS) medication and

hormone A hormone (from the Ancient Greek, Greek participle , "setting in motion") is a class of cell signaling, signaling molecules in multicellular organisms that are sent to distant organs or tissues by complex biological processes to regulate physio ...

which is used mainly in the treatment of low testosterone levels in men. It is also used to treat

breast development Breast development, also known as mammogenesis, is a complex biological process in primates that takes place throughout a female's life. It occurs across several phases, including prenatal development, puberty, and pregnancy. At menopause, breas ...

and small penis in males. Compared to

testosterone Testosterone is the primary male sex hormone and androgen in Male, males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testicles and prostate, as well as promoting se ...

, androstanolone (DHT) is less likely to aromatize into

estrogen Estrogen (also spelled oestrogen in British English; see spelling differences) is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three ...

, and therefore it shows less pronounced

ic side effects, such as

gynecomastia Gynecomastia (also spelled gynaecomastia) is the non-cancerous enlargement of one or both breasts in men due to the growth of breast tissue as a result of a hormone imbalance between estrogens and androgens. Updated by Brent Wisse (10 Novemb ...

and water retention. On the other hand, androstanolone (DHT) show more significant

androgenic An androgen (from Greek ''andr-'', the stem of the word meaning ) is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes ...

side effects, such as

acne Acne ( ), also known as ''acne vulgaris'', is a long-term Cutaneous condition, skin condition that occurs when Keratinocyte, dead skin cells and Sebum, oil from the skin clog hair follicles. Typical features of the condition include comedo, ...

hair loss Hair loss, also known as alopecia or baldness, refers to a loss of hair from part of the head or body. Typically at least the head is involved. The severity of hair loss can vary from a small area to the entire body. Inflammation or scarring ...

and

prostate enlargement Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, inability to urinate, or los ...

. It has strong

ic effects and muscle-building effects, as well as relatively weak

ic effects. It is typically given as a gel for application to the skin, but can also be used as an

ester In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distin ...

by injection into muscle.

Side effect In medicine, a side effect is an effect of the use of a medicinal drug or other treatment, usually adverse but sometimes beneficial, that is unintended. Herbal and traditional medicines also have side effects. A drug or procedure usually use ...

s of androstanolone include

symptom Signs and symptoms are diagnostic indications of an illness, injury, or condition. Signs are objective and externally observable; symptoms are a person's reported subjective experiences. A sign for example may be a higher or lower temperature ...

s of

masculinization Virilization or masculinization is the biological development of adult male characteristics in young males or females. Most of the changes of virilization are produced by androgens. Virilization is a medical term commonly used in three medical a ...

, increased hair growth, voice changes, and increased

sexual desire Sexual desire is an emotion and motivational state characterized by an interest in sexual objects or activities, or by a drive to seek out sexual objects or to engage in sexual activities. It is an aspect of sexuality, which varies significantly ...

. The medication is a

naturally occurring A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical ...

androgen and anabolic steroid and hence is an

agonist An agonist is a chemical that activates a Receptor (biochemistry), receptor to produce a biological response. Receptors are Cell (biology), cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an R ...

of the

androgen receptor The androgen receptor (AR), also known as NR3C4 (nuclear receptor subfamily 3, group C, member 4), is a type of nuclear receptor that is activated by binding any of the androgenic hormones, including testosterone and dihydrotestosterone, in th ...

(AR), the

biological target A biological target is anything within a living organism to which some other entity (like an endogenous ligand or a drug) is directed and/or binds, resulting in a change in its behavior or function. Examples of common classes of biological targets ...

of androgens like

and DHT. Androstanolone was discovered in 1935 and was introduced for medical use in 1953. It is used mostly in

France France, officially the French Republic, is a country located primarily in Western Europe. Overseas France, Its overseas regions and territories include French Guiana in South America, Saint Pierre and Miquelon in the Atlantic Ocean#North Atlan ...

and

Belgium Belgium, officially the Kingdom of Belgium, is a country in Northwestern Europe. Situated in a coastal lowland region known as the Low Countries, it is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeas ...

. The drug has been used by weightlifters to increase performance due to its powerful androgenic properties. The medication is a

controlled substance A controlled substance is generally a drug or chemical whose manufacture, possession and use is regulated by a government, such as illicitly used drugs or prescription medications that are designated by law. Some treaties, notably the Sing ...

in many countries and so non-medical use is generally illicit.

Medical uses

Androstanolone is available in

pharmaceutical Medication (also called medicament, medicine, pharmaceutical drug, medicinal product, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy ( pharmacotherapy) is an important part of the ...

formulation Formulation is a term used in various senses in various applications, both the material and the abstract or formal. Its fundamental meaning is the putting together of components in appropriate relationships or structures, according to a formula ...

s for

medical use Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...

as an androgen. It is used mainly as a form of

androgen replacement therapy Androgen replacement therapy (ART), often referred to as testosterone replacement therapy (TRT), is a form of hormone therapy in which androgens, often testosterone, are supplemented or replaced. It typically involves the administration of tes ...

in the treatment of male

hypogonadism Hypogonadism means diminished functional activity of the human gonad, gonads—the testicles or the ovary, ovaries—that may result in diminished biosynthesis, production of sex hormones. Low androgen (e.g., testosterone) levels are referred t ...

and is specifically approved for this indication in certain countries. However, it is no longer recommended for this purpose due to biological differences from testosterone such as lack of estrogenic effects and partial androgenic effects.

Topical A topical medication is a medication that is applied to a particular place on or in the body. Most often topical medication means application to body surfaces such as the skin or mucous membranes to treat ailments via a large range of classes ...

androstanolone is useful in the treatment of

. Similarly, androstanolone enanthate via

intramuscular injection Intramuscular injection, often abbreviated IM, is the medical injection, injection of a substance into a muscle. In medicine, it is one of several methods for parenteral, parenteral administration of medications. Intramuscular injection may be ...

has been found to be effective in the treatment persistent

pubertal Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a female, the testicles in a ...

. The medication has also been used as a topical gel to treat small penis in pre- and peripubertal boys with mild or

partial androgen insensitivity syndrome Partial androgen insensitivity syndrome (PAIS) is a condition that results in the partial inability of the Eukaryote#Animal cell, cell to respond to androgens. It is an X linked recessive condition. The partial unresponsiveness of the cell to the ...

. Androstanolone was found to be effective in the treatment of advanced

breast cancer Breast cancer is a cancer that develops from breast tissue. Signs of breast cancer may include a Breast lump, lump in the breast, a change in breast shape, dimpling of the skin, Milk-rejection sign, milk rejection, fluid coming from the nipp ...

in women in the 1950s, although it was used in very high doses and caused severe

virilization Virilization or masculinization is the biological development of adult male characteristics in young males or females. Most of the changes of virilization are produced by androgens. Virilization is a medical term commonly used in three medical a ...

. It was used as a

microcrystalline A microcrystalline material is a crystallized substance or rock that contains small crystals visible only through microscopic examination. There is little agreement on the range of crystal sizes that should be regarded as microcrystalline, but ...

aqueous suspension In chemistry, a suspension is a heterogeneous mixture of a fluid that contains solid particles sufficiently large for sedimentation. The particles may be visible to the naked eye, usually must be larger than one micrometer, and will eventually s ...

. Shortly thereafter, drostanolone propionate (2α-methylandrostanolone propionate) was developed for this use instead of androstanolone due to its superior

pharmacokinetics Pharmacokinetics (from Ancient Greek ''pharmakon'' "drug" and ''kinetikos'' "moving, putting in motion"; see chemical kinetics), sometimes abbreviated as PK, is a branch of pharmacology dedicated to describing how the body affects a specific su ...

and was introduced for this indication in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

and

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

in the early 1960s. Androstanolone was used at a dose of 25 mg sublingually two to three times per day in androgen replacement therapy for men. This is also the

anabolic Anabolism () is the set of metabolic pathways that construct macromolecules like DNA or RNA from smaller units. These reactions require energy, known also as an endergonic process. Anabolism is the building-up aspect of metabolism, whereas catab ...

dosage of androstanolone in men.

Available forms

Androstanolone is available as a 2.5% hydroalcoholic gel given transdermally in doses of 5 or 10 g/day (brand name Andractim). The medication was previously available as a 10 mg

oral The word oral may refer to: Relating to the mouth * Relating to the mouth, the first portion of the alimentary canal that primarily receives food and liquid **Oral administration of medicines ** Oral examination (also known as an oral exam or ora ...

tablet with 300 mg L-lysine (brand name Lysinex) and as a 25 mg

sublingual Sublingual (List of abbreviations used in medical prescriptions, abbreviated SL), from the Latin for "under the tongue", refers to the pharmacological route of administration by which substances diffuse into the blood through Tissue (biology), t ...

tablet (brand names Anabolex, Anaprotin, Anabolene, Anaboleen, Proteina). The medication has also been marketed in the form of several androstanolone esters, including androstanolone benzoate (brand names Ermalone-Amp, Hermalone, Sarcosan), androstanolone enanthate (brand name Anaboleen Depot), androstanolone propionate (brand name Pesomax), and

androstanolone valerate Androstanolone valerate (brand name Apeton), also known as stanolone valerate or dihydrotestosterone pentanoate, as well as 5α-androstan-17β-3-one 17β-valerate, is a synthetic androgen and anabolic steroid and a dihydrotestosterone ester. It i ...

(brand name Apeton), which are provided as

oil solution An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) and lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturat ...

s for

at regular intervals.

Side effects

Adverse effect An adverse effect is an undesired harmful effect resulting from a medication or other intervention, such as surgery. An adverse effect may be termed a "side effect", when judged to be secondary to a main or therapeutic effect. The term compli ...

s of androstanolone are similar to those of other AAS and include

ic side effects like

oily skin The human skin is the outer covering of the body and is the largest organ of the integumentary system. The skin has up to seven layers of ectodermal tissue guarding muscles, bones, ligaments and internal organs. Human skin is similar to most ...

seborrhea A sebaceous gland or oil gland is a microscopic exocrine gland in the skin that opens into a hair follicle to secrete an oily or waxy matter, called sebum, which lubricates the hair and skin of mammals. In humans, sebaceous glands occur in t ...

, increased

facial A facial is a family of skin care treatments for the face, including steam, exfoliation (physical and chemical), extraction, creams, lotions, facial masks, peels, and massage. They are normally performed in beauty salons, but are also a c ...

body hair Body hair or androgenic hair is terminal hair that develops on the human body during and after puberty. It is different from head hair and also from less visible vellus hair, which is much finer and lighter in color. Growth of androgenic hai ...

growth Growth may refer to: Biology *Auxology, the study of all aspects of human physical growth *Bacterial growth *Cell growth *Growth hormone, a peptide hormone that stimulates growth *Human development (biology) *Plant growth *Secondary growth, growt ...

scalp hair loss Pattern hair loss (also known as androgenetic alopecia (AGA)) is a hair loss condition that primarily affects the top and front of the scalp. In male-pattern hair loss (MPHL), the hair loss typically presents itself as either a receding front h ...

, and increased

aggressiveness Aggression is behavior aimed at opposing or attacking something or someone. Though often done with the intent to cause harm, some might channel it into creative and practical outlets. It may occur either reactively or without provocation. In h ...

and

sex drive In psychology, libido (; ) is psychic drive or energy, usually conceived of as sexual in nature, but sometimes conceived of as including other forms of desire. The term ''libido'' was originally developed by Sigmund Freud, the pioneering origin ...

. In women, androstanolone can cause partially irreversible

, for instance

voice deepening A voice change or voice mutation, sometimes referred to as a voice break or voice crack, commonly refers to the deepening of the voice of men as they reach puberty. Before puberty both sexes have roughly similar vocal pitches, but during puberty ...

hirsutism Hirsutism is excessive body hair on parts of the body where hair is normally absent or minimal. The word is from early 17th century: from Latin ''hirsutus'' meaning "hairy". It usually refers to a male pattern of hair growth in a female that ma ...

clitoromegaly Clitoromegaly (or macroclitoris) is an abnormal enlargement of the clitoris that is mostly congenital; it is otherwise acquired through deliberately induced clitoral enlargement, a form of body modification, by use of anabolic steroids, in parti ...

, breast atrophy, and

muscle hypertrophy Muscle hypertrophy or muscle building involves a hypertrophy or increase in size of skeletal muscle through a growth in size of its component cells. Two factors contribute to hypertrophy: sarcoplasmic hypertrophy, which focuses more on increa ...

, as well as

menstrual disturbance A menstrual disorder is characterized as any abnormal condition with regards to a woman's menstrual cycle. There are many different types of menstrual disorders that vary with signs and symptoms, including pain during menstruation, heavy bleeding, ...

s and reversible

infertility In biology, infertility is the inability of a male and female organism to Sexual reproduction, reproduce. It is usually not the natural state of a healthy organism that has reached sexual maturity, so children who have not undergone puberty, whi ...

. In men, the medication may also cause

testicular atrophy Testicular atrophy is a medical condition in which one or both testicles (or "testes") diminish in size and may be accompanied by reduced testicular function. Testicular atrophy is not related to the temporary shrinkage of the surrounding scrotum, ...

, and reversible infertility at sufficiently high dosages. Androstanolone can have adverse effects on the

cardiovascular system In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart a ...

, especially with long-term administration of high dosages. AAS like androstanolone stimulate

erythropoiesis Erythropoiesis (from Greek ''erythro'', meaning ''red'' and ''poiesis'', meaning ''to make'') is the process which produces red blood cells (erythrocytes), which is the development from erythropoietic stem cell to mature red blood cell. It is s ...

(

red blood cell Red blood cells (RBCs), referred to as erythrocytes (, with -''cyte'' translated as 'cell' in modern usage) in academia and medical publishing, also known as red cells, erythroid cells, and rarely haematids, are the most common type of blood cel ...

production) and increase

hematocrit The hematocrit () (Ht or HCT), also known by several other names, is the volume percentage (vol%) of red blood cells (RBCs) in blood, measured as part of a blood test. The measurement depends on the number and size of red blood cells. It is nor ...

levels and at high dosages can cause

polycythemia Polycythemia (also known as polycythaemia) is a laboratory finding in which the hematocrit (the volume percentage of red blood cells in the blood) and/or hemoglobin concentration are increased in the blood. Polycythemia is sometimes called erythr ...

(overproduction of red blood cells), which can greatly increase the risk of thrombic events such as

embolism An embolism is the lodging of an embolus, a blockage-causing piece of material, inside a blood vessel. The embolus may be a blood clot (thrombus), a fat globule (fat embolism), a bubble of air or other gas (air embolism, gas embolism), amniotic ...

and

stroke Stroke is a medical condition in which poor cerebral circulation, blood flow to a part of the brain causes cell death. There are two main types of stroke: brain ischemia, ischemic, due to lack of blood flow, and intracranial hemorrhage, hemor ...

. Unlike many other AAS, androstanolone is not aromatized into estrogens and hence has no risk of

ic side effects like

, fluid retention, or

edema Edema (American English), also spelled oedema (British English), and also known as fluid retention, swelling, dropsy and hydropsy, is the build-up of fluid in the body's tissue (biology), tissue. Most commonly, the legs or arms are affected. S ...

. In addition, as it is not a 17α-alkylated AAS and is administered parenterally, androstanolone has no risk of

hepatotoxicity Hepatotoxicity (from ''hepatic toxicity'') implies chemical-driven liver damage. Drug-induced liver injury (DILI) is a cause of acute and chronic liver disease caused specifically by medications and the most common reason for a drug to be withdr ...

. It has been theorized that androstanolone may have less risk of

benign prostatic hyperplasia Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, urinary retention, inability t ...

and

prostate cancer Prostate cancer is the neoplasm, uncontrolled growth of cells in the prostate, a gland in the male reproductive system below the bladder. Abnormal growth of the prostate tissue is usually detected through Screening (medicine), screening tests, ...

than testosterone because it is not aromatized into estrogens. This is relevant because estrogens are thought to possibly be necessary for the manifestation of these diseases. In accordance, androstanolone has been found to not increase

prostate gland The prostate is an male accessory gland, accessory gland of the male reproductive system and a muscle-driven mechanical switch between urination and ejaculation. It is found in all male mammals. It differs between species anatomically, chemica ...

size in men. Conversely, due to lack of aromatization into estrogens, androstanolone therapy for androgen replacement may result in decreased

bone mineral density Bone density, or bone mineral density, is the amount of bone mineral in bone tissue. The concept is of mass of mineral per volume of bone (relating to density in the physics sense), although clinically it is measured by proxy according to opti ...

, incomplete effects in the

brain The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for ...

, and undesirable changes in

cholesterol Cholesterol is the principal sterol of all higher animals, distributed in body Tissue (biology), tissues, especially the brain and spinal cord, and in Animal fat, animal fats and oils. Cholesterol is biosynthesis, biosynthesized by all anima ...

levels.

Pharmacology

Pharmacodynamics

Androstanolone is a potent

of the AR. It has an

affinity Affinity may refer to: Commerce, finance and law * Affinity (law), kinship by marriage * Affinity analysis, a market research and business management technique * Affinity Credit Union, a Saskatchewan-based credit union * Affinity Equity Pa ...

(K_d) of 0.25 to 0.5 nM for the human AR, which is about 2- to 3-fold higher than that of

(K_d = 0.4 to 1.0 nM) and the dissociation rate of androstanolone from the AR is also about 5-fold slower than that of testosterone. The EC₅₀ of androstanolone for activation of the AR is 0.13 nM, which is about 5-fold stronger than that of testosterone (EC₅₀ = 0.66 nM). In

bioassay A bioassay is an analytical method to determine the potency or effect of a substance by its effect on animal testing, living animals or plants (''in vivo''), or on living cells or tissues (''in vitro''). A bioassay can be either quantal or quantit ...

s, androstanolone has been found to be 2.5- to 10-fold more potent than testosterone. Upon intramuscular injection in rats, androstanolone is about 1.5- to 2.5-fold the potency of testosterone. Unlike testosterone and various other AAS, androstanolone cannot be aromatized, and for this reason, poses no risk of

side effect In medicine, a side effect is an effect of the use of a medicinal drug or other treatment, usually adverse but sometimes beneficial, that is unintended. Herbal and traditional medicines also have side effects. A drug or procedure usually use ...

s like

at any dosage. In addition, androstanolone cannot be

metabolized Metabolism (, from ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the co ...

by 5α-reductase (as it is already 5α-reduced), and for this reason, is not potentiated in so-called "androgenic" tissues like the

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different ...

hair follicle The hair follicle is an organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction betwee ...

s, and

, thereby improving its ratio of

ic effects. However, androstanolone is nonetheless described as a very poor anabolic agent. This is attributed to its high affinity as a

substrate Substrate may refer to: Physical layers *Substrate (biology), the natural environment in which an organism lives, or the surface or medium on which an organism grows or is attached ** Substrate (aquatic environment), the earthy material that exi ...

for 3α-hydroxysteroid dehydrogenase (3α-HSD), which is highly expressed in

skeletal muscle Skeletal muscle (commonly referred to as muscle) is one of the three types of vertebrate muscle tissue, the others being cardiac muscle and smooth muscle. They are part of the somatic nervous system, voluntary muscular system and typically are a ...

and inactivates androstanolone into 3α-androstanediol, a metabolite with very weak AR activity. Unlike androstanolone, testosterone is very resistant to metabolism by 3α-HSD, and so is not similarly inactivated in skeletal muscle. For the preceding reasons, androstanolone has been described as a "partial androgen".

Pharmacokinetics

Absorption

The

bioavailability In pharmacology, bioavailability is a subcategory of absorption and is the fraction (%) of an administered drug that reaches the systemic circulation. By definition, when a medication is administered intravenously, its bioavailability is 100%. H ...

of androstanolone differs considerably depending on its

route of administration In pharmacology and toxicology, a route of administration is the way by which a medication, drug, fluid, poison, or other substance is taken into the body. Routes of administration are generally classified by the location at which the substance ...

. Its

bioavailability is very low, and androstanolone has been considered to be ineffective by the oral route. However, it has been used orally, and is described as a weak AAS by this route. The

transdermal Transdermal is a route of administration wherein active ingredients are delivered across the skin for systemic distribution. Examples include transdermal patches used for medicine delivery. The drug is administered in the form of a patch or ointm ...

bioavailability of androstanolone is approximately 10%. Its bioavailability with

, on the other hand, is complete (100%). Doses of topical androstanolone gel of 16, 32, and 64 mg have been found to produce total testosterone and DHT levels in the low, mid, and high normal adult male range, respectively.

Distribution

The

plasma protein binding Plasma protein binding refers to the degree to which medications attach to blood proteins within the blood plasma. A drug's efficacy may be affected by the degree to which it binds. The less bound a drug is, the more efficiently it can traverse o ...

of androstanolone is about 98.5 to 99.0%. It is bound 50 to 80% to

sex hormone-binding globulin Sex hormone-binding globulin (SHBG) or sex steroid-binding globulin (SSBG) is a glycoprotein that binds to androgens and estrogens. When produced by the Sertoli cells in the seminiferous tubules of the testis, it is called androgen-binding prot ...

, 20 to 40% to

albumin Albumin is a family of globular proteins, the most common of which are the serum albumins. All of the proteins of the albumin family are water- soluble, moderately soluble in concentrated salt solutions, and experience heat denaturation. Alb ...

, and less than 0.5% to

corticosteroid-binding globulin Transcortin, also known as corticosteroid-binding globulin (CBG) or serpin A6, is a protein produced in the liver in animals. In humans it is encoded by the SERPINA6 gene. It is an alpha-globulin. Function This gene encodes an alpha-globulin ...

, with about 1.0 to 1.5% circulating freely or unbound.

Metabolism

The

terminal half-life Biological half-life (elimination half-life, pharmacological half-life) is the time taken for concentration of a biological substance (such as a medication) to decrease from its maximum concentration ( Cmax) to half of Cmax in the blood plasma. ...

of androstanolone in the circulation (53 minutes) is longer than that of testosterone (34 minutes), and this may account for some of the difference in their potency. A study of transdermal androstanolone and testosterone therapy reported terminal half-lives of 2.83 hours and 1.29 hours, respectively.

Chemistry

Androstanolone, also known as 5α-androstan-17β-ol-3-one or as 5α-dihydrotestosterone (5α-DHT), is a

androstane Androstane is a C19 steroidal hydrocarbon with a gonane core. Androstane can exist as either of two isomers, known as 5α-androstane and 5β-androstane. File:androstane.png, 5α-Androstane File:androstane 5beta.png, 5β-Androstane Pharmacolog ...

steroid A steroid is an organic compound with four fused compound, fused rings (designated A, B, C, and D) arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes t ...

with a

ketone group In organic chemistry, a ketone is an organic compound with the structure , where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group (a carbon-oxygen double bond C=O). The simplest ketone is acetone ( ...

at the C3 position and a

hydroxyl group In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...

at the C17β position. It is the

derivative In mathematics, the derivative is a fundamental tool that quantifies the sensitivity to change of a function's output with respect to its input. The derivative of a function of a single variable at a chosen input value, when it exists, is t ...

of testosterone in which the

double bond In chemistry, a double bond is a covalent bond between two atoms involving four bonding electrons as opposed to two in a single bond. Double bonds occur most commonly between two carbon atoms, for example in alkenes. Many double bonds exist betw ...

between the C4 and C5 positions has been

reduced Reduction, reduced, or reduce may refer to: Science and technology Chemistry * Reduction (chemistry), part of a reduction-oxidation (redox) reaction in which atoms have their oxidation state changed. ** Organic redox reaction, a redox reacti ...

hydrogenated Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organi ...

Esters

Several C17β

prodrug A prodrug is a pharmacologically inactive medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be ...

s of androstanolone, including androstanolone benzoate, androstanolone enanthate, androstanolone propionate, and

, have been developed and introduced for medical use as AAS. Conversely,

dihydrotestosterone acetate Dihydrotestosterone acetate, also known as androstanolone acetate or stanolone acetate, as well as 5α-dihydrotestosterone 17β-acetate, is a synthetic androgen and anabolic steroid and a dihydrotestosterone ester This is a list of androgen es ...

, dihydrotestosterone butyrate, and dihydrotestosterone formate have been developed but have not been marketed.

Derivatives

Synthetic Synthetic may refer to: Science * Synthetic biology * Synthetic chemical or compound, produced by the process of chemical synthesis * Synthetic elements, chemical elements that are not naturally found on Earth and therefore have to be created in ...

derivatives of androstanolone (DHT) that have been developed as AAS include: ; Non-17α-alkylated derivatives * Marketed **

Bolazine Bolazine (), also known as 2α-methyl-5α-androstan-17β-ol-3-one azine, is a synthetic androgen/anabolic steroid (AAS) of the dihydrotestosterone (DHT) group which was never marketed. It is not orally active and is used as the ester prodrug bo ...

(an

azine Azines are a functional class of organic compounds with the connectivity . These compounds are the product of the condensation of hydrazine with ketones and aldehydes, although in practice they are often made by alternative routes. Ketazines a ...

dimer Dimer may refer to: * Dimer (chemistry), a chemical structure formed from two similar sub-units ** Protein dimer, a protein quaternary structure ** d-dimer ** TH-dimer * Dimer model, an item in statistical mechanics, based on ''domino tiling'' * ...

prodrug of drostanolone) **

Drostanolone Drostanolone, or dromostanolone, is an anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which was never marketed. An androgen ester prodrug of drostanolone, drostanolone propionate, was formerly used in the treatmen ...

(2α-methyl-DHT) **

Epitiostanol Epitiostanol, sold under the brand name Thiodrol, is an injected antiestrogen and anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which was described in the literature in 1965 and has been marketed in Japan as an an ...

(2α,3α-epithio-DHT) **

Mepitiostane Mepitiostane, sold under the brand name Thioderon, is an orally active antiestrogen and anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which is marketed in Japan as an antineoplastic agent for the treatment of breas ...

(a 17-

ether In organic chemistry, ethers are a class of compounds that contain an ether group, a single oxygen atom bonded to two separate carbon atoms, each part of an organyl group (e.g., alkyl or aryl). They have the general formula , where R and R� ...

of epitiostanol) **

Mesterolone Mesterolone, sold under the brand name Proviron among others, is an androgen and anabolic steroid (AAS) medication which is used mainly in the treatment of low testosterone levels. It has also been used to treat male infertility, although this ...

(1α-methyl-DHT) **

Metenolone Metenolone, or methenolone, is an androgen and anabolic steroid (AAS) which is used in the form of esters such as metenolone acetate (brand name Primobolan, Nibal) and metenolone enanthate (brand name Primobolan Depot, Nibal Injection). Meten ...

(1-methyl-δ¹-DHT) **

Stenbolone Stenbolone is an anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which was never marketed. A C17β ester prodrug of stenbolone, stenbolone acetate, is used as an AAS for depot intramuscular injection under the brand n ...

(2-methyl-δ¹-DHT) * Never marketed ** 1-Testosterone (dihydroboldenone; δ¹-DHT) **

Mesabolone Mesabolone, also known as 1-testosterone 17β-methoxycyclopentyl ether, is a synthetic anabolic–androgenic steroid (AAS) that was never marketed. It is the 17β-(1-methoxycyclohexane) ether In organic chemistry, ethers are a class of compo ...

(a 17-ether prodrug of δ¹-DHT) **

Prostanozol Prostanozol, also known as demethylstanozolol tetrahydropyran ether, is an androgen/anabolic steroid (AAS) and designer steroid which acts as a prodrug of the 17α-demethylated analogue of stanozolol (Winstrol). It was found in 2005 as an ingre ...

(a 17-ether prodrug of 17α-demethylstanozolol) ; 17α-Alkylated derivatives * Marketed **

Androisoxazole Androisoxazole (brand names Androxan, Neo-Ponden, Neo-Pondus), also known as 17α-methyl-5α-androstano,2-csoxazol-17β-ol, is an orally active anabolic-androgenic steroid (AAS) and a 17α-alkylated derivative of dihydrotestosterone (DHT) that ...

(a 2,3-

isoxazole Isoxazole is an electron-rich azole with an oxygen atom next to the nitrogen. It is also the class of compounds containing this ring. Isoxazolyl is the Valence (chemistry), univalent functional group derived from isoxazole. Occurrence Isoxazole ri ...

A ring-fused derivative of 17α-methyl-DHT) **

Furazabol Furazabol (, ) (brand names Frazalon, Miotalon, Qu Zhi Shu), also known as androfurazanol, is a synthetic, orally active anabolic-androgenic steroid which has been marketed in Japan since 1969. It is a 17α-alkylated derivative of dihydrotestos ...

(a 2,3-

furan Furan is a Heterocyclic compound, heterocyclic organic compound, consisting of a five-membered aromatic Ring (chemistry), ring with four carbon Atom, atoms and one oxygen atom. Chemical compounds containing such rings are also referred to as f ...

A ring-fused derivative of 17α-methyl-DHT) ** Mebolazine (an azine dimer prodrug of methasterone) ** Mestanolone (17α-methyl-DHT) **

Oxandrolone Oxandrolone is an androgen and synthetic anabolic steroid (AAS) medication to help promote weight gain in various situations, to help offset protein catabolism caused by long-term corticosteroid therapy, to support recovery from severe burns, t ...

(2-oxa-17α-methyl-DHT) **

Oxymetholone Oxymetholone, sold under the brand names Anadrol and Anapolon among others, is an androgen and anabolic steroid (AAS) medication which is used primarily in the treatment of anemia. It is also used to treat osteoporosis, HIV/AIDS wasting syndr ...

(2-hydroxymethylene-17α-methyl-DHT) **

Stanozolol Stanozolol (Abbreviation, abbrev. Stz), sold under many brand names, is a synthetic androgen and anabolic steroid (AAS) medication derived from dihydrotestosterone (DHT). It is used to treat hereditary angioedema. It was developed by American ph ...

(a 2,3-

pyrazole Pyrazole is an organic compound with the chemical formula, formula . It is a heterocycle characterized as an azole with a 5-membered ring of three carbon atoms and two adjacent nitrogen atoms, which are in Arene substitution pattern, ortho-substi ...

A ring-fused derivative of 17α-methyl-DHT) * Never marketed **

Desoxymethyltestosterone Desoxymethyltestosterone (DMT), known by the nicknames Madol and Pheraplex, is a synthetic compound, synthetic and oral administration, orally active anabolic–androgenic steroid (AAS) and a 17α-alkylated anabolic steroid, 17α-methylated chemi ...

(3-deketo-17α-methyl-δ²-DHT) ** Methasterone (2α,17α-dimethyl-DHT) ** Methyl-1-testosterone (methyldihydroboldenone; 17α-methyl-δ¹-DHT) **

Methylepitiostanol Methylepitiostanol, known by the nicknames Epistane, Hemapolin, Havoc, and Epi Plex, is a synthetic and orally active anabolic–androgenic steroid (AAS) of the dihydrotestosterone (DHT) group which was first described in the literature in 197 ...

(2α,3α-epithio-17α-methyl-DHT) ** Methylstenbolone (2,17α-dimethyl-δ¹-DHT)

History

Androstanolone was first discovered and synthesized in 1935 by

Adolf Butenandt Adolf Friedrich Johann Butenandt (; 24 March 1903 – 18 January 1995) was a German biochemist. He was awarded the Nobel Prize in Chemistry in 1939 for his "work on sex hormones." He initially rejected the award in accordance with government pol ...

and his colleagues. It was first introduced for medical use in 1953, under the brand name ''Neodrol'' in the

, and was subsequently marketed in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

and other

an countries. Transdermal androstanolone gel has been available in

since 1982.

Society and culture

Generic names

When used as a drug, androstanolone is referred to as ''androstanolone'' () or as ''stanolone'' () rather than as DHT.

Brand names

Brand names of androstanolone include Anaboleen, Anabolex, Anaprotin (), Andractim (formerly AndroGel-DHT) (, , ), Androlone, Apeton, Gelovit (), Neodrol, Ophtovital (), Pesomax (), Stanaprol, and Stanolone, among others.

Availability

The availability of pharmaceutical androstanolone is limited; it is not available in the

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

, but it is or has been available in certain

an countries, including the

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

Spain Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Eur ...

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

, and

Luxembourg Luxembourg, officially the Grand Duchy of Luxembourg, is a landlocked country in Western Europe. It is bordered by Belgium to the west and north, Germany to the east, and France on the south. Its capital and most populous city, Luxembour ...

. The available formulations of androstanolone include buccal or

tablets (Anabolex, Stanolone),

topical gels Topical gels are a Topical medication, topical drug delivery dosage form commonly used in cosmetics and treatments for skin diseases because of their advantages over cream and ointment. They are formed from a mixture of Thickening agent, gelator, so ...

(Andractim, Gelovit, Ophtovital), and, as

s in

oil An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) and lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturate ...

injectable An injection (often and usually referred to as a "shot" in US English, a "jab" in UK English, or a "jag" in Scottish English and Scots) is the act of administering a liquid, especially a drug, into a person's body using a needle (usually a hyp ...

s like androstanolone propionate (Pesomax) and

(Apeton). Androstanolone benzoate (Ermalone-Amp, Hermalone, Sarcosan) and androstanolone enanthate (Anaboleen Depot) are additional androstanolone esters that are available for medical use in some countries. Androstanolone esters act as

s of androstanolone in the body and have a long-lasting

depot Depot may refer to: Places * Depot, Poland, a village * Depot Glacier (disambiguation) * Depot Island (disambiguation) * Depot Nunatak * Depot Peak Brands and enterprises * Maxwell Street Depot, a restaurant in Chicago, United States * Of ...

effect when given via

Legal status

Androstanolone, along with other AAS, is a schedule III

in the

under the

Controlled Substances Act The Controlled Substances Act (CSA) is the statute establishing federal government of the United States, federal drug policy of the United States, U.S. drug policy under which the manufacture, importation, possession, use, and distribution of ...

. Androstanolone is on the

World Anti-Doping Agency The World Anti-Doping Agency (WADA; , AMA) is an international organization co-founded by the governments of over 140 nations along with the International Olympic Committee based in Canada to promote, coordinate, and monitor the fight against d ...

's list of prohibited substances, and is therefore banned from use in most major sports.

Research

In the early- to mid-2000s, transdermal or topical androstanolone was under development in the

for the treatment of

(as a form of

), male

osteoporosis Osteoporosis is a systemic skeletal disorder characterized by low bone mass, micro-architectural deterioration of bone tissue leading to more porous bone, and consequent increase in Bone fracture, fracture risk. It is the most common reason f ...

, and

cachexia Cachexia () is a syndrome that happens when people have certain illnesses, causing muscle loss that cannot be fully reversed with improved nutrition. It is most common in diseases like cancer, Heart failure, congestive heart failure, chronic o ...

(in

cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...

patients) and in

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

for the treatment of

(BPH). It reached phase II

clinical trial Clinical trials are prospective biomedical or behavioral research studies on human subject research, human participants designed to answer specific questions about biomedical or behavioral interventions, including new treatments (such as novel v ...

s for hypogonadism and BPH and phase III clinical studies for cachexia but development was ultimately never completed for these indications in these specific countries. Although androstanolone itself has not been approved for cachexia in any country, an orally active

synthetic Synthetic may refer to: Science * Synthetic biology * Synthetic chemical or compound, produced by the process of chemical synthesis * Synthetic elements, chemical elements that are not naturally found on Earth and therefore have to be created in ...

of androstanolone,

oxandrolone Oxandrolone is an androgen and synthetic anabolic steroid (AAS) medication to help promote weight gain in various situations, to help offset protein catabolism caused by long-term corticosteroid therapy, to support recovery from severe burns, t ...

(2-oxa-17α-methylandrostanolone), is approved and used for this indication in the United States. Topical androgens like androstanolone have been used and studied in the treatment of

cellulite Cellulite () or gynoid lipodystrophy (GLD) is the herniation of subcutaneous fat within fibrous connective tissue that manifests as skin dimpling and nodularity, often on the pelvic region (specifically the buttocks), lower limbs, and abdomen. C ...

in women. Topical androstanolone on the abdomen has also been found to significantly decrease subcutaneous abdominal fat in women, and hence may be useful for improving body silhouette. However, men and hyperandrogenic women have higher amounts of abdominal fat than healthy women, and androgen therapy has been found to increase abdominal fat in

postmenopausal Menopause, also known as the climacteric, is the time when menstrual periods permanently stop, marking the end of the reproductive stage for the female human. It typically occurs between the ages of 45 and 55, although the exact timing can ...

women and

transgender men A trans man or transgender man is a man who was assigned female at birth. Trans men have a male gender identity, and many trans men undergo medical and social transition to alter their appearance in a way that aligns with their gender identi ...

References

External links

*
Androstanolone (for hypogonadism and cachexia) - AdisInsight

Androstanolone (for hypogonadism and BPH) - AdisInsight

Androstanolone (for male osteoporosis) - AdisInsight
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Pharmacodynamics Pharmacodynamics (PD) is the study of the biochemistry, biochemical and physiology, physiologic effects of drugs (especially pharmaceutical drugs). The effects can include those manifested within animals (including humans), microorganisms, or comb ...

, titlestyle = background:#ccccff , list1 = {{Androgen receptor modulators {{Estrogen receptor modulators {{GABAA receptor positive allosteric modulators 5α-Reduced steroid metabolites Secondary alcohols Anabolic–androgenic steroids Androstanes Estrogens GABAA receptor positive allosteric modulators Ketones Testosterone