Minocycline, sold under the brand name Minocin among others, is a tetracycline antibiotic medication used to treat a number of bacterial infections such as some occurring in certain forms of

pneumonia Pneumonia is an Inflammation, inflammatory condition of the lung primarily affecting the small air sacs known as Pulmonary alveolus, alveoli. Symptoms typically include some combination of Cough#Classification, productive or dry cough, ches ...

. It is generally (but not always) less preferred than the tetracycline

doxycycline Doxycycline is a Broad-spectrum antibiotic, broad-spectrum antibiotic of the Tetracycline antibiotics, tetracycline class used in the treatment of infections caused by bacteria and certain parasites. It is used to treat pneumonia, bacterial p ...

. Minocycline is also used for the treatment of

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, ...

and

rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects synovial joint, joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and h ...

. It is taken

by mouth Oral administration is a route of administration whereby a substance is taken through the Human mouth, mouth, swallowed, and then processed via the digestive system. This is a common route of administration for many medications. Oral administ ...

or applied to 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 ...

. Common side effects include nausea, diarrhea, dizziness, allergic reactions, and kidney problems. Serious side effects may include

anaphylaxis Anaphylaxis (Greek: 'up' + 'guarding') is a serious, potentially fatal allergic reaction and medical emergency that is rapid in onset and requires immediate medical attention regardless of the use of emergency medication on site. It typicall ...

, a

lupus Lupus, formally called systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Common ...

-like syndrome, and easy sunburning. Use in the later part of

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 ...

may harm the baby and safety during

breastfeeding Breastfeeding, also known as nursing, is the process where breast milk is fed to a child. Infants may suck the milk directly from the breast, or milk may be extracted with a Breast pump, pump and then fed to the infant. The World Health Orga ...

is unclear. It works by decreasing a bacterium's ability to make protein thus stopping its growth. Minocycline was patented in 1961 and came into commercial use in 1971. It is available as a

generic medication A generic drug is a pharmaceutical drug that contains the same chemical substance as a drug that was originally protected by chemical patents. Generic drugs are allowed for sale after the patents on the original drugs expire. Because the active ch ...

. In 2022, it was the 269th most commonly prescribed medication in the United States, with more than 900,000 prescriptions.

Medical uses

Acne

Minocycline and

are frequently used for the treatment of

acne vulgaris 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, ...

. Minocycline is specifically

indicated In medicine, an indication is a valid reason to use a certain test, medication, procedure, or surgery. There can be multiple indications to use a procedure or medication. An indication can commonly be confused with the term diagnosis. A diagnosis ...

to treat inflammatory lesions of non-nodular moderate to severe acne vulgaris in people nine years of age and older. Both minocycline and doxycycline have similar levels of effectiveness and common adverse effects for acne, although doxycycline may have a slightly lower risk of adverse side effects. Both

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 ...

/ systemic and more recently

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 ...

formulations of minocycline are available to treat acne. Historically, oral minocycline has been an effective treatment for acne vulgaris. However, acne that is caused by antibiotic-resistant bacteria is a growing problem in many countries. In Europe and North America, a number of people with acne no longer respond well to treatment with

tetracycline Tetracycline, sold under various brand names, is an antibiotic in the tetracyclines family of medications, used to treat a number of infections, including acne, cholera, brucellosis, plague, malaria, and syphilis. It is available in oral an ...

family antibiotics because their acne symptoms are caused by bacteria (primarily ''

Cutibacterium acnes ''Cutibacterium acnes'' (''Propionibacterium acnes'') is the relatively slow-growing, typically aerotolerant anaerobic, gram-positive bacterium (rod) linked to the skin condition of acne; it can also cause chronic blepharitis and endophthalmitis ...

'') that are resistant to these antibiotics. In order to reduce resistance rates as well as increase the effectiveness of treatment, oral antibiotics should be generally combined with topical acne creams such as benzoyl peroxide or a retinoid (

tretinoin Tretinoin, also known as all-''trans'' retinoic acid (ATRA), is a medication used for the treatment of acne and acute promyelocytic leukemia. For acne, it is applied to the skin as a cream, gel or ointment. For acute promyelocytic leukemia, ...

adapalene Adapalene, sold under the brand name Differin among others, is a third-generation topical retinoid primarily used in the treatment of mild-moderate acne, and is also used off-label to treat keratosis pilaris as well as other skin conditions. S ...

, etc.). There have also been concerns about systemic minocycline having a variety of rare adverse effects in terms of its use to treat acne. Oral minocycline is used to treat acne for up to 3 to 4months. Data beyond 3 to 4months are limited.

Other infections

Minocycline is also used for other skin infections such as methicillin-resistant ''Staphylococcus aureus''. Although minocycline's broader spectrum of activity, compared with other members of the group, includes activity against ''

Neisseria meningitidis ''Neisseria meningitidis'', often referred to as the meningococcus, is a Gram-negative bacterium that can cause meningitis and other forms of meningococcal disease such as meningococcemia, a life-threatening sepsis. The bacterium is referred to a ...

'', its use for

prophylaxis Preventive healthcare, or prophylaxis, is the application of healthcare measures to prevent diseases.Hugh R. Leavell and E. Gurney Clark as "the science and art of preventing disease, prolonging life, and promoting physical and mental health a ...

is no longer recommended because of side effects (

dizziness Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to Balance disorder, disequilibrium or a non-specific feeling, such as giddiness or foolishness. Dizziness is a ...

and

vertigo Vertigo is a condition in which a person has the sensation that they are moving, or that objects around them are moving, when they are not. Often it feels like a spinning or swaying movement. It may be associated with nausea, vomiting, perspira ...

). It may be used to treat certain strains of methicillin-resistant ''S. aureus'' infection and a disease caused by drug-resistant ''

Acinetobacter ''Acinetobacter'' is a genus of Gram-negative bacteria belonging to the wider class of Gammaproteobacteria. ''Acinetobacter'' species are oxidase-negative, exhibit twitching motility, and occur in pairs under magnification. They are important ...

'' spp. A list of uses includes: *

Amoebic dysentery Amoebiasis, or amoebic dysentery, is an infection of the intestines caused by a parasitic amoeba '' Entamoeba histolytica''. Amoebiasis can be present with no, mild, or severe symptoms. Symptoms may include lethargy, loss of weight, coloni ...

Anthrax Anthrax is an infection caused by the bacterium '' Bacillus anthracis'' or ''Bacillus cereus'' biovar ''anthracis''. Infection typically occurs by contact with the skin, inhalation, or intestinal absorption. Symptom onset occurs between one ...

Bubonic plague Bubonic plague is one of three types of Plague (disease), plague caused by the Bacteria, bacterium ''Yersinia pestis''. One to seven days after exposure to the bacteria, flu-like symptoms develop. These symptoms include fever, headaches, and ...

Cholera Cholera () is an infection of the small intestine by some Strain (biology), strains of the Bacteria, bacterium ''Vibrio cholerae''. Symptoms may range from none, to mild, to severe. The classic symptom is large amounts of watery diarrhea last ...

* Ehrlichiosis *

Gonorrhea Gonorrhoea or gonorrhea, colloquially known as the clap, is a sexually transmitted infection (STI) caused by the bacterium ''Neisseria gonorrhoeae''. Infection may involve the genitals, mouth, or rectum. Gonorrhea is spread through sexual c ...

(when

penicillin Penicillins (P, PCN or PEN) are a group of beta-lactam antibiotic, β-lactam antibiotics originally obtained from ''Penicillium'' Mold (fungus), moulds, principally ''Penicillium chrysogenum, P. chrysogenum'' and ''Penicillium rubens, P. ru ...

cannot be given) * Gougerot-Carteaud syndrome ( confluent and reticulated papillomatosis) *

Hidradenitis suppurativa Hidradenitis suppurativa (HS), sometimes known as acne inversa or Verneuil's disease, is a long-term dermatological condition characterized by the occurrence of inflamed and swollen lesions, lumps. These are typically painful and break open, r ...

* For use as an adjuvant to

HAART The management of HIV/AIDS normally includes the use of multiple antiretroviral drugs as a strategy to control HIV infection. There are several classes of antiretroviral agents that act on different stages of the HIV life-cycle. The use of mu ...

Leprosy Leprosy, also known as Hansen's disease (HD), is a Chronic condition, long-term infection by the bacteria ''Mycobacterium leprae'' or ''Mycobacterium lepromatosis''. Infection can lead to damage of the Peripheral nervous system, nerves, respir ...

Periodontal disease Periodontal disease, also known as gum disease, is a set of inflammatory conditions affecting the tissues surrounding the teeth. In its early stage, called gingivitis, the gums become swollen and red and may bleed. It is considered the main c ...

* Perioral dermatitis * Respiratory infections such as

Rocky Mountain spotted fever Rocky Mountain spotted fever (RMSF) is a bacterial disease spread by ticks. It typically begins with a fever and headache, which is followed a few days later with the development of a rash. The rash is generally Petechial rash, made up of small s ...

Rosacea Rosacea is a long-term skin condition that typically affects the face. It results in redness, pimples, swelling, and small and superficial dilated blood vessels. Often, the nose, cheeks, forehead, and chin are most involved. A red, en ...

Syphilis Syphilis () is a sexually transmitted infection caused by the bacterium ''Treponema pallidum'' subspecies ''pallidum''. The signs and symptoms depend on the stage it presents: primary, secondary, latent syphilis, latent or tertiary. The prim ...

(when penicillin cannot be given) *

Urinary tract infection A urinary tract infection (UTI) is an infection that affects a part of the urinary tract. Lower urinary tract infections may involve the bladder (cystitis) or urethra (urethritis) while upper urinary tract infections affect the kidney (pyel ...

s (UTIs), rectal infections, and infections of the

cervix The cervix (: cervices) or cervix uteri is a dynamic fibromuscular sexual organ of the female reproductive system that connects the vagina with the uterine cavity. The human female cervix has been documented anatomically since at least the time ...

caused by certain microbes Minocycline has been reported to be effective in the eradication of UTIs and

prostatitis Prostatitis is an umbrella term for a variety of medical conditions that incorporate bacterial and non-bacterial origin illnesses in the pelvic region. In contrast with the plain meaning of the word (which means "inflammation of the prostate"), the ...

. A 2013

Cochrane review Cochrane is a British international charitable organisation formed to synthesize medical research findings to facilitate evidence-based choices about health interventions involving health professionals, patients and policy makers. It includes ...

identified and included two comparative

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 of minocycline for chronic bacterial prostatitis. For this condition, minocycline has been found to be equivalent or superior to

, equivalent to

trimethoprim/sulfamethoxazole Trimethoprim/sulfamethoxazole, sold under the trade names Bactrim, Cotrim (a short form of the British Approved Name, Co-trimoxazole) and Septra, among others, is a fixed-dose combination antibiotic medication used to treat a variety of bacte ...

, and superior to the first-generation

cephalosporin The cephalosporins (sg. ) are a class of β-lactam antibiotics originally derived from the fungus '' Acremonium'', which was previously known as ''Cephalosporium''. Together with cephamycins, they constitute a subgroup of β-lactam antibio ...

cephalexin. It was also equivalent to the fluoroquinolone

ofloxacin Ofloxacin is a quinolone antibiotic useful for the treatment of a number of bacterial infections. When taken Oral administration, by mouth or intravenous, injection into a vein, these include pneumonia, cellulitis, urinary tract infections, prost ...

in the treatment of chronic bacterial prostatitis caused by '' Ureaplasma urealyticum''. Treatment durations of minocycline for chronic bacterial prostatitis have ranged from 2 to 4weeks.

Other uses

Both minocycline and doxycycline have shown effectiveness in

asthma Asthma is a common long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wh ...

due to immune-suppressing effects. Minocycline and doxycycline have modest effectiveness in treating

. However, the 2015

American College of Rheumatology The American College of Rheumatology (ACR; until 1985 called American Rheumatism Association) is an organization of and for physicians, health professionals, and scientists that advances rheumatology through programs of education, research, advocac ...

guideline for the treatment of rheumatoid arthritis does not include minocycline.

Available forms

Minocycline is available in the form of 50 and 100mg

capsules, among a variety of other formulations. The oral form of minocycline is usually taken twice daily, once every 12hours, although divided doses four times daily can also be employed. Extended-release oral forms are also available. A

formulation is available as well.

Contraindications

The drug is

contraindicated In medicine, a contraindication is a condition (a situation or factor) that serves as a reason not to take a certain medical treatment due to the harm that it would cause the patient. Contraindication is the opposite of indication, which is a rea ...

in people with known

hypersensitivity Hypersensitivity (also called hypersensitivity reaction or intolerance) is an abnormal physiological condition in which there is an undesirable and adverse immune response to an antigen. It is an abnormality in the immune system that causes Imm ...

to tetracycline antibiotics, as there is complete cross sensitivity in this group. It is also contraindicated in people with severe liver impairment and after the 16th week of

Side effects

Minocycline may cause

upset stomach Abdominal pain, also known as a stomach ache, is a symptom associated with both non-serious and serious medical issues. Since the abdomen contains most of the body's vital organs, it can be an indicator of a wide variety of diseases. Given th ...

diarrhea Diarrhea (American English), also spelled diarrhoea or diarrhœa (British English), is the condition of having at least three loose, liquid, or watery bowel movements in a day. It often lasts for a few days and can result in dehydration d ...

, unsteadiness,

drowsiness Somnolence (alternatively sleepiness or drowsiness) is a state of strong desire for sleep, or sleeping for unusually long periods (compare hypersomnia). It has distinct meanings and causes. It can refer to the usual state preceding falling asleep ...

mouth sores A mouth ulcer (aphtha), or sometimes called a canker sore or salt blister, is an Ulcer (dermatology), ulcer that occurs on the mucous membrane of the oral cavity. Mouth ulcers are very common, occurring in association with many diseases and by ma ...

migraines Migraine (, ) is a complex neurological disorder characterized by episodes of moderate-to-severe headache, most often unilateral and generally associated with nausea, and light and sound sensitivity. Other characterizing symptoms may includ ...

, and

vomiting Vomiting (also known as emesis, puking and throwing up) is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be the result of ailments like food poisoning, gastroenteritis, pre ...

. It increases sensitivity to sunlight, and may affect the quality of sleep and rarely causes

sleep disorder A sleep disorder, or somnipathy, is a medical disorder affecting an individual's sleep patterns, sometimes impacting physical, mental, social, and emotional functioning. Polysomnography and actigraphy are tests commonly ordered for diagnosing sle ...

s. It has also been linked to cases of lupus. Prolonged use of minocycline can lead to blue-gray staining of skin, fingernails, and scar tissue. This staining is not permanent, but can take a very long time for the skin color to return to normal; however, a muddy brown skin color in sun-exposed areas is usually permanent. Permanent blue discoloration of gums or teeth discoloration may also occur. Rare but serious side effects include

fever Fever or pyrexia in humans is a symptom of an anti-infection defense mechanism that appears with Human body temperature, body temperature exceeding the normal range caused by an increase in the body's temperature Human body temperature#Fever, s ...

, yellowing of the eyes or skin, stomach pain, sore throat, vision changes, and mental changes, including

depersonalization Depersonalization is a dissociative phenomenon characterized by a subjective feeling of detachment from oneself, manifesting as a sense of disconnection from one's thoughts, emotions, sensations, or actions, and often accompanied by a feeling of ...

. Occasionally, minocycline therapy may result in

autoimmune disorder An autoimmune disease is a condition that results from an anomalous response of the adaptive immune system, wherein it mistakenly targets and attacks healthy, functioning parts of the body as if they were foreign organisms. It is estimated tha ...

s such as drug-related

and

autoimmune hepatitis Autoimmune hepatitis, formerly known as lupoid hepatitis, plasma cell hepatitis, or autoimmune chronic active hepatitis, is a chronic, autoimmune disease of the liver that occurs when the body's immune system attacks liver cells, causing the liv ...

, which usually occurs in men who also developed minocycline-induced lupus; however, women are more likely to develop minocycline-induced lupus. Significant or complete recovery occurs in most people who develop minocycline-induced autoimmune problems within a period of a few weeks to a year of cessation of minocycline therapy. Autoimmune problems emerge during chronic therapy, but can sometimes occur after only short courses of a couple of weeks of therapy.

Drug reaction with eosinophilia and systemic symptoms Drug rash with eosinophilia and systemic symptoms or drug reaction with eosinophilia and systemic symptoms (DRESS), also termed drug-induced hypersensitivity syndrome (DIHS), is a rare reaction to certain medications. It involves primarily a wi ...

(DRESS) syndrome can occur during the first few weeks of therapy with minocycline. Minocycline, but not other tetracyclines, can cause vestibular disturbances, including symptoms of

ataxia Ataxia (from Greek α- negative prefix+ -τάξις rder= "lack of order") is a neurological sign consisting of lack of voluntary coordination of muscle movements that can include gait abnormality, speech changes, and abnormalities in e ...

, and

tinnitus Tinnitus is a condition when a person hears a ringing sound or a different variety of sound when no corresponding external sound is present and other people cannot hear it. Nearly everyone experiences faint "normal tinnitus" in a completely ...

. These effects are thought to be related to minocycline's greater penetration into the

central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain, spinal cord and retina. The CNS is so named because the brain integrates the received information and coordinates and influences the activity o ...

. The vestibular side effects are much more common in women than in men, reportedly occurring in 50 to 70% of women receiving minocycline. However, other sources state that vestibular side effects occur in only 1 to 10% of patients. In any case, other studies have found that side effects occur more frequently in women than in men (~58% vs. 34%, respectively). Due to its vestibular side effects, minocycline has been said to be rarely used in female patients. Minocycline's vestibular side effects typically resolve after discontinuation of the drug. Symptoms of an

allergic reaction Allergies, also known as allergic diseases, are various conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include Allergic rhinitis, hay fever, Food allergy, food al ...

include

rash A rash is a change of the skin that affects its color, appearance, or texture. A rash may be localized in one part of the body, or affect all the skin. Rashes may cause the skin to change color, itch, become warm, bumpy, chapped, dry, cracke ...

, itching, swelling, severe dizziness, and trouble breathing. Minocycline has also been reported to very rarely cause

idiopathic intracranial hypertension Idiopathic intracranial hypertension (IIH), previously known as pseudotumor cerebri and benign intracranial hypertension, is a condition characterized by increased intracranial pressure (pressure around the brain) without a detectable cause. The m ...

(pseudotumor cerebri), a side effect also more common in female patients, potentially leading to permanent vision damage if not recognized early and treated. Contrary to most other tetracycline antibiotics (

excluded), minocycline may be used in those with kidney disease, but may aggravate

systemic lupus erythematosus Lupus, formally called systemic lupus erythematosus (SLE), is an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue in many parts of the body. Symptoms vary among people and may be mild to severe. Common ...

. It may also trigger or unmask

. Minocycline can cause the rare condition of secondary intracranial hypertension, which has initial symptoms of headache, visual disturbances, dizziness, vomiting, and confusion. Brain swelling and

are rare side effects of minocycline in some people. Minocycline, like most tetracyclines, becomes dangerous past its expiration date."Principles and methods for the assessment of nephrotoxicity associated with exposure to chemicals". Environmental health criteria: 119. World Health Organization (WHO). . ISSN 0250-863X. 1991 While most prescription drugs lose potency after their expiration dates, tetracyclines are known to become toxic over time. Expired tetracyclines can cause serious damage to the kidney due to the formation of a degradation product, anhydro-4-epitetracycline. Minocycline's absorption is impaired if taken at the same time of day as calcium or iron supplements. Unlike some of the other tetracycline group antibiotics, it can be taken with calcium-rich foods such as milk, although this does reduce the absorption slightly. Minocycline, like other tetracyclines, is associated with esophageal irritation and ulceration if insufficient fluids are taken with the drug before sleep. A 2007 study suggested that minocycline harms

amyotrophic lateral sclerosis Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND) or—in the United States—Lou Gehrig's disease (LGD), is a rare, Terminal illness, terminal neurodegenerative disease, neurodegenerative disorder that results i ...

(ALS) patients. Patients on minocycline declined more rapidly than those on placebo. The mechanism of this side effect is unknown, although a hypothesis is that the drug exacerbated an autoimmune component of the primary disease. The effect does not seem to be dose-dependent because the patients on high doses did not do worse than those on the low doses. Other possible rare side effects of minocycline include

hyperpigmentation Hyperpigmentation, also known as the dark spots or circles on the skin, is the darkening of an area of Human skin, skin or nail (anatomy), nails caused by increased melanin. Causes Hyperpigmentation can be caused by sun damage, inflammation, or ...

and hypersensitivity reactions, among others. It has been associated with more rare and serious adverse effects than other tetracyclines. Some of the rare adverse effects of minocycline may result in death. This has spurred interest in topical instead of systemic minocycline for treatment of acne. Minocycline is another drug known to cause

leukopenia Leukopenia () is a decrease in the number of white blood cells (leukocytes). It places individuals at increased risk of infection as white blood cells are the body's primary defense against infections. Signs and symptoms Symptoms may include: * s ...

. Minocycine has shown

thyroid The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans, it is a butterfly-shaped gland located in the neck below the Adam's apple. It consists of two connected lobes. The lower two thirds of the lobes are connected by ...

toxicity in animals, including in rodents, mini pigs, dogs, and monkeys. The use of minocycline to treat acne has been associated with skin and gut

dysbiosis Dysbiosis (also called dysbacteriosis) is characterized by a disruption to the microbiome resulting in an imbalance in the microbiota, changes in their functional composition and metabolic activities, or a shift in their local distribution. For e ...

(see antibiotic misuse).

Overdose

Symptoms of minocycline

overdose A drug overdose (overdose or OD) is the ingestion or application of a drug or other substance in quantities much greater than are recommended. Retrieved on September 20, 2014.

may include

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 ...

, and

. There is no specific

antidote An antidote is a substance that can counteract a form of poisoning. The term ultimately derives from the Greek term φάρμακον ἀντίδοτον ''(pharmakon antidoton)'', "(medicine) given as a remedy". An older term in English which is ...

for overdose of minocycline and treatment should be symptom-based and supportive. The drug is not removed by

hemodialysis Hemodialysis, American and British English spelling differences#ae and oe, also spelled haemodialysis, or simply ''"'dialysis'"'', is a process of filtering the blood of a person whose kidneys are not working normally. This type of Kidney dialys ...

peritoneal dialysis Peritoneal dialysis (PD) is a type of kidney dialysis, dialysis that uses the peritoneum in a person's abdomen as the membrane through which fluid and dissolved substances are exchanged with the blood. It is used to remove excess fluid, correct e ...

Interactions

The combination of minocycline with dairy, antacids, calcium and magnesium supplements, iron products, laxatives containing magnesium, or

bile acid sequestrant The bile acid sequestrants are a group of resins used to bind certain components of bile in the gastrointestinal tract. They disrupt the enterohepatic circulation of bile acids by combining with bile constituents and preventing their reabsorption f ...

s may decrease minocycline's effectiveness by forming

chelate Chelation () is a type of bonding of ions and their molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate (multiple bonded) ligand and a single central metal atom. These l ...

s. Combining it with

isotretinoin Isotretinoin, also known as 13-''cis''-retinoic acid and sold under the brand name Accutane among others, is a medication used to treat skin diseases like harlequin-type ichthyosis, and lamellar ichthyosis, and severe cystic acne or moderat ...

, acitretin or other

retinoid The retinoids are a class of chemical compounds that are natural derivatives of vitamin A or are chemically related to it. Synthetic retinoids are utilized in cosmetic formulations, clinical dermatology, and the treatment of some forms of cancer ...

s can increase the risk for intracranial hypertension. Minocycline significantly reduces concentrations of the anti-HIV drug atazanavir in the body.

Pharmacology

Pharmacodynamics

Antibiotic activity

Minocycline mediates its

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting pathogenic bacteria, bacterial infections, and antibiotic medications are widely used in the therapy ...

activity by binding to the 30S ribosomal subunit of

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

and thereby inhibiting protein synthesis. It is primarily

bacteriostatic A bacteriostatic agent or bacteriostat, abbreviated Bstatic, is a biological or chemical agent that stops bacteria from reproducing, while not necessarily killing them otherwise. Depending on their application, bacteriostatic antibiotics, disinfec ...

. The drug is a broad-spectrum antibiotic and shows activity against a wide range of both

Gram-positive In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. The Gram stain is ...

and

Gram-negative bacteria Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the Crystal violet, crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelo ...

Other activities

Minocycline shows a number of off-target activities in addition to its antibiotic activity. These include

inhibition Inhibitor or inhibition may refer to: Biology * Enzyme inhibitor, a substance that binds to an enzyme and decreases the enzyme's activity * Reuptake inhibitor, a substance that increases neurotransmission by blocking the reuptake of a neurotransm ...

matrix metalloproteinase Matrix metalloproteinases (MMPs), also known as matrix metallopeptidases or matrixins, are metalloproteinases that are calcium-dependent zinc-containing endopeptidases; other family members are adamalysins, serralysins, and astacins. The MMPs be ...

s (MMPs),

anti-inflammatory Anti-inflammatory is the property of a substance or treatment that reduces inflammation, fever or swelling. Anti-inflammatory drugs, also called anti-inflammatories, make up about half of analgesics. These drugs reduce pain by inhibiting mechan ...

effects, antiapoptotic effects,

antioxidant Antioxidants are Chemical compound, compounds that inhibit Redox, oxidation, a chemical reaction that can produce Radical (chemistry), free radicals. Autoxidation leads to degradation of organic compounds, including living matter. Antioxidants ...

effects, and neuroprotective effects. Some other reported activities of minocycline include: * PARP1

''K''_i = 13.8nM *

Neuroprotection Neuroprotection refers to the relative preservation of neuronal structure and/or function. In the case of an ongoing insult (a neurodegenerative insult) the relative preservation of neuronal integrity implies a reduction in the rate of neuronal l ...

IC₅₀ = 10nM *

Microglia Microglia are a type of glia, glial cell located throughout the brain and spinal cord of the central nervous system (CNS). Microglia account for about around 5–10% of cells found within the brain. As the resident macrophage cells, they act as t ...

full inhibition = 20nM * Suppression of the

mouse A mouse (: mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus'' ...

's locomotor activity = 0.5mg/kg * Indirect inhibition of inducible nitric oxide synthase

Pharmacokinetics

Absorption

Minocycline is quickly and nearly completely absorbed from the upper part of the

small intestine The small intestine or small bowel is an organ (anatomy), organ in the human gastrointestinal tract, gastrointestinal tract where most of the #Absorption, absorption of nutrients from food takes place. It lies between the stomach and large intes ...

. Taking it together with food, including milk, has no relevant influence on resorption. It reaches highest

blood plasma Blood plasma is a light Amber (color), amber-colored liquid component of blood in which blood cells are absent, but which contains Blood protein, proteins and other constituents of whole blood in Suspension (chemistry), suspension. It makes up ...

concentrations after 1 to 2hours.

Distribution

The drug has a

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 70 to 75%. It penetrates into almost all tissues; very high concentrations are found in the

gallbladder In vertebrates, the gallbladder, also known as the cholecyst, is a small hollow Organ (anatomy), organ where bile is stored and concentrated before it is released into the small intestine. In humans, the pear-shaped gallbladder lies beneath t ...

and liver. It crosses the

blood–brain barrier The blood–brain barrier (BBB) is a highly selective semipermeable membrane, semipermeable border of endothelium, endothelial cells that regulates the transfer of solutes and chemicals between the circulatory system and the central nervous system ...

better than

and other tetracyclines, reaching therapeutically relevant concentrations in the

cerebrospinal fluid Cerebrospinal fluid (CSF) is a clear, colorless Extracellular fluid#Transcellular fluid, transcellular body fluid found within the meninges, meningeal tissue that surrounds the vertebrate brain and spinal cord, and in the ventricular system, ven ...

and also in inflamed

meninges In anatomy, the meninges (; meninx ; ) are the three membranes that envelop the brain and spinal cord. In mammals, the meninges are the dura mater, the arachnoid mater, and the pia mater. Cerebrospinal fluid is located in the subarachnoid spac ...

. Minocycline achieves good concentrations in the

urinary The human urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressu ...

bladder The bladder () is a hollow organ in humans and other vertebrates that stores urine from the kidneys. In placental mammals, urine enters the bladder via the ureters and exits via the urethra during urination. In humans, the bladder is a distens ...

, and many other tissues. It shows excellent penetration into the

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 ...

. However, while permeation of prostate tissue and semen is good, levels are lower in prosatic fluid.

Metabolism

Minocycline is inactivated by

metabolism 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 ...

in the liver to about 50%. It is primarily metabolized into 9-hydroxyminocycline. Two ''N''-

demethylated Demethylation is the chemical process resulting in the removal of a methyl group (CH3) from a molecule. A common way of demethylation is the replacement of a methyl group by a hydrogen atom, resulting in a net loss of one carbon and two hydrogen at ...

metabolites are also formed.

Elimination

The rest is predominantly excreted into the gut (in part via the gallbladder, in part directly from blood vessels) and eliminated via the feces. About 10–15% are eliminated via the kidneys. It is excreted about 5 to 10% unchanged in urine. For comparison, other tetracyclines, like doxycycline and tetracycline, are excreted 30 to 70% unchanged in urine. The

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

of minocycline is 11 to 26hours in healthy people, up to 30hours in those with

kidney failure Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney fa ...

, and significantly longer in those with

liver disease Liver disease, or hepatic disease, is any of many diseases of the liver. If long-lasting it is termed chronic liver disease. Although the diseases differ in detail, liver diseases often have features in common. Liver diseases File:Ground gla ...

Chemistry

Minocycline is a

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 ...

. It is closely structurally related to other tetracyclic antibiotics such as

, and

tigecycline Tigecycline, sold under the brand name Tygacil, is a tetracycline antibiotic medication for a number of bacterial infections. It is a glycylcycline class drug that is administered intravenously. It was developed in response to the growing ra ...

. The drug is used in form of minocycline hydrochloride

dihydrate In chemistry, a hydrate is a substance that contains water or its constituent elements. The chemical state of the water varies widely between different classes of hydrates, some of which were so labeled before their chemical structure was understo ...

, which is sparingly

soluble In chemistry, solubility is the ability of a substance, the solute, to form a solution with another substance, the solvent. Insolubility is the opposite property, the inability of the solute to form such a solution. The extent of the solubi ...

in water and slightly soluble in

ethanol Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...

. Minocycline reacts acidic in aqueous solution. The

partition coefficient In the physical sciences, a partition coefficient (''P'') or distribution coefficient (''D'') is the ratio of concentrations of a chemical compound, compound in a mixture of two immiscible solvents at partition equilibrium, equilibrium. This rati ...

(P) of minocycline has been reported to be 39.4 (i.e., log P of 1.60). However, other sources have stated the experimental log P of minocycline to be 0.05, 0.5, and 1.1. In any case, minocycline is consistently described as a highly

lipophilic Lipophilicity (from Greek language, Greek λίπος "fat" and :wikt:φίλος, φίλος "friendly") is the ability of a chemical compound to dissolve in fats, oils, lipids, and non-polar solvents such as hexane or toluene. Such compounds are c ...

compound with excellent tissue penetration and

distribution Distribution may refer to: Mathematics *Distribution (mathematics), generalized functions used to formulate solutions of partial differential equations *Probability distribution, the probability of a particular value or value range of a varia ...

. It has been said to be unique among the tetracyclines in that it is the most lipophilic of all of the members of this group. Minocycline has 10 to 30times greater lipophilicity than tetracycline and 5times greater lipophilicity than doxycycline. The improved lipophilicity of minocycline is thought to be advantageous in terms of its clinical antibiotic effectiveness.

History

Minocycline was patented in 1961, was first described in the scientific literature in 1967, and came into commercial use in 1971. A

foam Foams are two-phase materials science, material systems where a gas is dispersed in a second, non-gaseous material, specifically, in which gas cells are enclosed by a distinct liquid or solid material. Note, this source focuses only on liquid ...

for treatment of

was approved in 2019.

Society and culture

Brand names

* Minomycin * Minostad (in Europe, for the treatment of

) * Akamin * Minocin * Minoderm * Cyclimycin * Arestin (1-mg doses administered locally into periodontal pockets, after

scaling and root planing Scaling and root planing, also known as conventional periodontal therapy, non-surgical periodontal therapy or deep cleaning, is a procedure involving removal of dental plaque and calculus (scaling or debridement) and then smoothing, or planing, ...

, for treatment of periodontal disease.) * Nomika (in Indonesia) * Aknemin * Solodyn (extended-release, for the treatment of acne) * Dynacin * Sebomin * Mino-Tabs * Acnamino * Minopen (in Japan) * Maracyn 2 (for treatment of bacterial infections in aquarium fish and amphibians) * Quatrocin (in Syria) * Minox (in Ireland) * Minoz (in India and Romania) * Divaine (in India) * Vinocyclin 100 (100-mg dose approved for treatment of acne in Vietnam) * Dentomycin (2% minocylcine gel for use in periodontal pockets) * Amzeeq (4% foam, approved for treatment of acne United States) * Zilxi (1.5% foam, approved for treatment of rosacea in the United States) * Cleeravue-M

Generic availability

It is available as a

Research

Neuropsychiatric disorders

Depression

Minocycline has been studied in the treatment of depression. According to a 2023

systematic review A systematic review is a scholarly synthesis of the evidence on a clearly presented topic using critical methods to identify, define and assess research on the topic. A systematic review extracts and interprets data from published studies on ...

of minocycline for

treatment-resistant depression Treatment-resistant depression (TRD) is often defined as major depressive disorder in which an affected person does not respond adequately to at least two different antidepressant medications at an adequate dose and for an adequate duration. Inad ...

based on four clinical trials, "There is no significant difference with minocycline compared to placebo for depression not responding to first-line antidepressant therapy." Likewise, a 2025 systematic review and

meta-analysis Meta-analysis is a method of synthesis of quantitative data from multiple independent studies addressing a common research question. An important part of this method involves computing a combined effect size across all of the studies. As such, th ...

of four

randomized controlled trial A randomized controlled trial (or randomized control trial; RCT) is a form of scientific experiment used to control factors not under direct experimental control. Examples of RCTs are clinical trials that compare the effects of drugs, surgical ...

s found that minocycline was not significantly more effective than placebo in treating depression. Minocycline might have some benefit in treatment-resistant depression with

inflammation Inflammation (from ) is part of the biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. The five cardinal signs are heat, pain, redness, swelling, and loss of function (Latin ''calor'', '' ...

however. Yet another meta-analysis, also published in 2023, found that minocycline was effective in the treatment of depression, including treatment-resistant depression, with a small to moderate

effect size In statistics, an effect size is a value measuring the strength of the relationship between two variables in a population, or a sample-based estimate of that quantity. It can refer to the value of a statistic calculated from a sample of data, the ...

Schizophrenia

Early research has found a tentative benefit from minocycline in

schizophrenia Schizophrenia () is a mental disorder characterized variously by hallucinations (typically, Auditory hallucination#Schizophrenia, hearing voices), delusions, thought disorder, disorganized thinking and behavior, and Reduced affect display, f ...

, with several trials underway as of 2012. A 2014 meta-analysis found minocycline may reduce negative and total symptom scores and was well tolerated. A 2019 meta-analysis, which included 13 randomized controlled trials, found that minocycline was effective in the treatment of the positive, negative, and general symptoms of schizophrenia, with small to moderate effect sizes. Similarly, a 2023 systematic review and meta-analysis of 10 randomized controlled trials found that minocycline was effective in treating the total, negative, and general symptoms of schizophrenia but not the positive or cognitive symptoms, again with small to moderate effect sizes.

Other conditions

Some early studies suggest that minocycline may be beneficial as an add-on treatment for moderate-to-severe obsessive-compulsive disorder (OCD) when used with a

selective serotonin reuptake inhibitor Selective serotonin reuptake inhibitors (SSRIs) are a class of drugs that are typically used as antidepressants in the treatment of major depressive disorder, anxiety disorders, and other psychological conditions. SSRIs primarily work by blo ...

(SSRI).

Stroke and neurodegenerative diseases

In ongoing research and trial, minocycline demonstrated efficacy and seems a promising neuroprotective agent in acute

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 ...

patients, especially in AIS subgroup. Further RCTs are needed to evaluate the efficacy and safety of minocycline among ICH patients. Research is examining the possible neuroprotective and anti-inflammatory effects of minocycline against the progression of a group of

neurodegenerative disorder A neurodegenerative disease is caused by the progressive loss of neurons, in the process known as neurodegeneration. Neuronal damage may also ultimately result in their death. Neurodegenerative diseases include amyotrophic lateral sclerosis, mul ...

s including

multiple sclerosis Multiple sclerosis (MS) is an autoimmune disease resulting in damage to myelinthe insulating covers of nerve cellsin the brain and spinal cord. As a demyelinating disease, MS disrupts the nervous system's ability to Action potential, transmit ...

Huntington's disease Huntington's disease (HD), also known as Huntington's chorea, is an incurable neurodegenerative disease that is mostly Genetic disorder#Autosomal dominant, inherited. It typically presents as a triad of progressive psychiatric, cognitive, and ...

, and

Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a neurodegenerative disease primarily of the central nervous system, affecting both motor system, motor and non-motor systems. Symptoms typically develop gradually and non-motor issues become ...