Estradiol benzoate butyrate (EBB), sold under the brand names Neolutin N, Redimen, Soluna, and Unijab and formerly known under the developmental code name Unimens, is an

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 ...

medication which is used in

hormonal birth control Hormonal contraception refers to birth control methods that act on the endocrine system. Almost all methods are composed of steroid hormones, although in India one selective estrogen receptor modulator is marketed as a contraceptive. The origin ...

for women. It is formulated in combination with dihydroxyprogesterone acetophenide (DHPA; algestone acetophenide), a

progestin A progestogen, also referred to as a progestagen, gestagen, or gestogen, is a type of medication which produces effects similar to those of the natural female sex hormone progesterone in the body. A progestin is a '' synthetic'' progestogen. ...

, and is used specifically as a

combined injectable contraceptive Combined injectable contraceptives (CICs) are a form of hormonal birth control for women. They consist of monthly injections of combined formulations containing an estrogen and a progestin to prevent pregnancy. CICs are different from progestog ...

. EBB is not available for medical use alone. The medication, in combination with DHPA, is given by injection into muscle once a month.

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 EBB include

breast tenderness Breast pain is the symptom of discomfort in either one or both breasts. Pain in both breasts is often described as ''breast tenderness'', is usually associated with the menstrual period and is not serious. Pain that involves only one part of a ...

, breast enlargement,

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. It can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the throat. Over 30 d ...

headache A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe ...

, and fluid retention. EBB is an

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

estrogen receptor Estrogen receptors (ERs) are proteins found in cell (biology), cells that function as receptor (biochemistry), receptors for the hormone estrogen (17β-estradiol). There are two main classes of ERs. The first includes the intracellular estrogen ...

, 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 ...

s like

estradiol Estradiol (E2), also called oestrogen, oestradiol, is an estrogen steroid hormone and the major female sex hormone. It is involved in the regulation of female reproductive cycles such as estrous and menstrual cycles. Estradiol is responsible ...

. It is an

estrogen ester An estrogen ester is an ester of an estrogen, most typically of estradiol but also of other estrogens such as estrone, estriol, and even nonsteroidal estrogens like diethylstilbestrol. Esterification renders estradiol into a prodrug of estradiol ...

and a

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 ...

in the body. Because of this, it is considered to be a

natural Nature is an inherent character or constitution, particularly of the ecosphere or the universe as a whole. In this general sense nature refers to the laws, elements and phenomena of the physical world, including life. Although humans are part ...

and bioidentical form of estrogen. EBB was first described in 1938. It was developed for use as a form of birth control in the 1970s and was introduced for medical use for this indication by the 1980s. The medication is used in combination with DHPA as a combined injectable contraceptive in

Peru Peru, officially the Republic of Peru, is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the south and west by the Pac ...

and

Singapore Singapore, officially the Republic of Singapore, is an island country and city-state in Southeast Asia. The country's territory comprises one main island, 63 satellite islands and islets, and one outlying islet. It is about one degree ...

Medical uses

EBB is used in combination with DHPA as a once-a-month

to prevent

pregnancy Pregnancy is the time during which one or more offspring gestation, gestates inside a woman's uterus. A multiple birth, multiple pregnancy involves more than one offspring, such as with twins. Conception (biology), Conception usually occurs ...

in women.

Available forms

The combination of EBB and DHPA contains 10 mg estradiol benzoate butyrate (EBB), an

, and 150 mg

algestone acetophenide Algestone acetophenide, also known more commonly as dihydroxyprogesterone acetophenide (DHPA) and sold under the brand names Perlutal and Topasel among others, is a progestin medication which is used in combination with an estrogen as a form ...

(dihydroxyprogesterone acetophenide; DHPA), a

Side effects

The combination of EBB and DHPA is said to be associated with poor control of menstrual bleeding when used as a once-a-month combined injectable contraceptive.

Pharmacology

Pharmacodynamics

EBB is an

estradiol ester This is a list of estrogen esters, or ester prodrugs of estrogens. It includes esters, as well as ethers, of steroidal estrogens like estradiol, estrone, and estriol and of nonsteroidal estrogens like the stilbestrols diethylstilbestrol an ...

, or a

. As such, it is an

, or an

of the

s. EBB is of about 64% higher

molecular weight A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemi ...

than estradiol due to the presence of its C3

benzoate Benzoic acid () is a white (or colorless) solid organic compound with the formula , whose structure consists of a benzene ring () with a carboxyl () substituent. The benzoyl group is often abbreviated "Bz" (not to be confused with "Bn," which ...

and C17β

butyrate The conjugate acids are in :Carboxylic acids. {{Commons category, Carboxylate ions, Carboxylate anions Carbon compounds Anions ...

esters. Because EBB is a prodrug of estradiol, it is considered to be a

and bioidentical form of estrogen. The estrogenic

potency Potency may refer to: * Potency (pharmacology), a measure of the activity of a drug in a biological system * Virility * Cell potency, a measure of the differentiation potential of stem cells * In homeopathic dilutions, potency is a measure of ho ...

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 ...

ethinylestradiol Ethinylestradiol (EE) is an estrogen medication which is used widely in birth control pills in combination with progestins. Ethinylestradiol was widely used for various indications such as the treatment of menopausal symptoms, gynecological ...

is approximately 30-fold higher than that of

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

EBB. In accordance, 50 μg/day oral ethinylestradiol has been reported to be about 3 times stronger in estrogenic effect than once-a-month injections of 10 mg EBB.

Pharmacokinetics

A single 10 mg

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 ...

of EBB has a duration of approximately 3 weeks. Its duration is shorter than that of estradiol enantate. A preliminary study of the duration of EBB relative to other estradiol esters was conducted in 1952.

Chemistry

EBB is a

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 ...

estrane Estrane is a C18 steroid derivative, with a gonane core. ''Estrenes'' are estrane derivatives that contain a double bond, with an example being nandrolone. ''Estratrienes'' (estrins) are estrane derivatives that contain three double bonds, for i ...

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 ...

and the C3

(benzenecarboxylate) and C17β

butyrate The conjugate acids are in :Carboxylic acids. {{Commons category, Carboxylate ions, Carboxylate anions Carbon compounds Anions ...

(butanoate)

diester 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 distinc ...

. It is also known as estradiol 3-benzoate 17β-n-butyrate or as estra-1,3,5(10)-triene-3,17β-diol 3-benzoate 17β-n-butyrate. The experimental octanol/water partition coefficient (logP) of EBB is 6.3.

History

EBB, along with a variety of other

s, was first described in 1938 by Karl Miescher and colleagues of Ciba in

Basel, Switzerland Basel ( ; ), also known as Basle ( ), ; ; ; . is a city in northwestern Switzerland on the river Rhine (at the transition from the High to the Upper Rhine). Basel is Switzerland's third-most-populous city (after Zurich and Geneva), with ...

. It was developed in combination with DHPA as a combined injectable contraceptive in the 1970s. The combination was marketed for use as a combined injectable contraceptive in

by 1987.

Society and culture

Brand names

EBB is marketed in combination with DHPA under the brand names Neolutin N, Redimen, Soluna, and Unijab. It was originally developed under the tentative brand name Unimens, but ultimately was not marketed under this particular brand name.

Availability

The combination of EBB and DHPA is available only in

and

References

{{Estrogen receptor modulators Benzoate esters Butyrate esters Estradiol esters Synthetic estrogens