Minocycline is a second-generation antibiotic in the tetracycline class of antibiotics. Second-generation, in this case, means that it is a semi-synthetic compound; first-generation tetracyclines are naturally occurring compounds, and second-generation tetracyclines have been slightly modified, but still closely resemble the original compound. Another common second-generation tetracycline is doxycycline; for more information on how minocycline and doxycycline compare, see the article Minocycline vs. Doxycycline.
What are Tetracycline Antibiotics and What are They Used For?
Tetracycline antibiotics are broad-spectrum antibiotics; this means that they treat many different kinds of bacteria. It also means that it is often considered when doctors aren’t exactly sure what bacterium is causing an infection because there is a high likelihood that a tetracycline antibiotic will work.
Tetracycline antibiotics are bacteriostatic: they don’t kill bacteria outright, but instead, prevent them from making necessary proteins and multiplying. Because bacterial cells must multiply for the bacterial colony to survive, the colony eventually dies and the infection is cured.
First discovered in the 1950s, tetracycline antibiotics were initially used to treat acne. However, tetracyclines, and more specifically, minocycline, can do much more than just treat infections as a medicine.
What is Minocycline Used For?
Like all tetracyclines, minocycline has many uses, with several being discovered or looked at in clinical studies more recently.
Minocycline was originally created to fight acne. Unfortunately, even though the side effect profile was better than its predecessors, minocycline still had some undesirable side effects or drug interactions and wasn’t proven to work any better than the other tetracycline-type antibiotics for treating acne. Minocycline has since been developed into an extended-release formulation, marketed under the name Solodyn, and is still used to treat acne; however, it does have some drawbacks.
Minocycline cannot be used with another common acne treatment, isotretinoin, due to a drug interaction that can cause pseudotumor cerebri, a type of increased pressure around the brain. Pseudotumor cerebri is also sometimes called idiopathic intracranial hypertension, or IIH.
Additionally, minocycline is often prescribed as an acne treatment for adolescents and adults. However, minocycline, like all tetracyclines, can decrease the effectiveness of birth control pills, ultimately leading to unwanted pregnancies if no backup method of contraception is used.
Angiogenesis is the formation of new blood vessels. Minocycline has been shown to prevent the formation of new blood vessels, which is beneficial in treating everything from rosacea to cancer.
As previously mentioned, minocycline is an antibiotic. Minocycline is a broad-spectrum antibiotic, meaning it is active against many different types of bacteria. However, the most common use for bacterial infections is in the treatment of sexually transmitted diseases, specifically chlamydia.
Minocycline has also shown significant promise in the treatment of Lyme Disease, specifically against the Borrelia species that cause Lyme Disease.
Minocycline was proven to have anti-inflammatory properties very early after its development. Historically, it has been used to treat periodontal disease, an inflammatory condition of the gums and teeth that leads to tooth detachment and loss. It has also been shown to help reduce inflammation from atherosclerosis, as well as in the skin condition dermatitis. It has also been shown to have antioxidant properties, which aid in its anti-inflammatory effectIVENESS as well as in other areas. Other anti-inflammatory benefits of minocycline are discussed in greater detail in other sections.
Minocycline has been used in several studies to demonstrate a benefit in arthritis and rheumatoid arthritis. Specifically, minocycline interferes with enzymes that break down collagen, a protein important for the connective tissues in the joints. In clinical studies, minocycline was shown to reduce joint pain and inflammation in arthritic conditions, including rheumatoid arthritis, as well as c-reactive protein (CRP), a biomarker for inflammation.
Minocycline has also been shown to reduce the inflammation associated with irritable bowl diseases like IBS, though this may be as much due to changes in the microbiome of the gut in addition to any anti-inflammatory properties of the medication.
In addition to prevention of angiogenesis, a necessary step for tumor growth and metastasis in cancer, minocycline has been shown to help regulate apoptosis, or pre-programmed cell death. In cancer, normal apoptosis is altered, allowing cancer cells to grow and spread, leading to the formation of tumors. By helping regulate normal apoptosis, minocycline creates an unfavorable environment for cancer and tumors to develop and grow.
Minocycline has been shown to have neuroprotective effects, which have been observed on the brain, spinal cord, and peripheral nerves. These neuroprotective effects are beneficial to patients recovering from many different neurological issues, including: ischemic stroke, traumatic brain injury, Alzheimer’s Disease, Huntington’s Disease, amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), spinal cord injuries, and Parkinson’s Disease.
Due to its anti-inflammatory properties, neuroprotective evidence, and other effects, minocycline is a promising candidate for the treatment of pain. More specifically, minocycline is being studied in neuropathic pain, bone cancer pain, chemotherapy-induced pain, and several other kinds of chronic pain.
Researchers are also looking into the benefits of minocycline in the treatment of psychiatric illnesses, particularly depression and bipolar disorder. Microglia, the immune system of the brain, are often overactive in depression and bipolar disorder, and through a series of complex interactions can impact mood and neurotransmitter processing in the brain. Minocycline has demonstrated an ability to inhibit the activation of microglia, which not only reduces the impact they have on mood but also seems to boost the effectiveness of antidepressant medications.
Minocycline is currently being studied for other important potential uses. Because of its neuroprotective and anti-inflammatory properties, minocycline is being researched as an adjunct therapy in the treatment of COVID-19.
Minocycline has also shown promise in the treatment and prevention of HIV and AIDS, as studies have demonstrated that it can prevent the replication of the HIV virus.
Finally, minocycline is being studied in degenerative diseases of the bone and other conditions that lead to decreases in bone mass, as minocycline appears to be able to prevent bone resorption, or the breaking down of bone.
How Can I Take Minocycline?
There are four main forms of minocycline currently available: capsules, oral solution, injections or intravenous (IV), and topical forms (usually a lotion, gel, or foam) available in the USA. Minocycline capsules are taken by mouth as prescribed by your doctor or pharmacist, while the oral solution can be taken once or twice per day depending on your condition. A prescription is needed for all forms. There can also be varying dosages and strengths in regards to different forms of the medication. For example, there are products available that are extended-release tablets or capsules and this can affect your dosage and how often you may take the medication. Minocycline should not be mixed with any other antibiotics or antifungal medicines without speaking to your healthcare provider.
Minocycline is a promising drug for the treatment of many different conditions, however, it does come with some side effects that you should be aware of before taking minocycline. It should be stated that different methods of taking this medicine can have different side effects. For example, oral minocycline use can have different side effects than if you took the topical solution so it is important to learn about all of the adverse effects.
Minocycline is generally well-tolerated in adults and children over 8 years old; however, there are potential side effects to be aware of should you take this medicine. The common side effects include:
- nausea or vomiting (this may occur more often if taken on an empty stomach),
- dizziness or lightheadedness
- allergic reactions
- kidney problems
In rare cases, if you take minocycline you are also at risk for some serious side effects too, which include:
- photosensitivity or sensitivity to sunlight which may make you burn easier
- anaphylaxis, which is a quick onset allergic reaction that can include itchiness, dizziness, low blood pressure, throat and tongue swelling, and shortness of breath among other things
There are some additional factors that your doctor should know before prescribing minocycline. If you’re allergic to minocycline, sulfa antibiotics or tartrazine, you should not take this medicine. Women who are pregnant or breastfeeding shouldn’t take minocycline either. Minocycline has been shown to cause harm to the developing fetus and can be secreted in breast milk so avoid taking it if you’re pregnant or plan on becoming pregnant or breastfeeding in the near future.
The use of this medicine can cause any of these adverse reactions. Should you experience any of these symptoms from the use of minocycline we urge you to seek medical help.
Like all antibiotics, minocycline requires a prescription in the United States, and many of the benefits discussed above are currently being studied and not yet approved by the FDA. For more information about minocycline, talk to a healthcare provider or check out one of the Read this Next articles below. Should you think minocycline is right for you, we encourage you to talk to your doctor, physician, or pharmacist to see if a prescription is needed. If you experience any of the common side effects or have an allergic reaction, we encourage you to seek medical attention immediately.
References, Studies and Sources
Dean OM, Data-Franco J, Giorlando F, Berk M. Minocycline. CNS Drugs. 2012/05/01 2012;26(5):391-401. doi:10.2165/11632000-000000000-00000
Garner SE, Eady A, Bennett C, Newton JN, Thomas K, Popescu CM. Minocycline for acne vulgaris: efficacy and safety. Cochrane Database of Systematic Reviews. 2012;(8)doi:10.1002/14651858.CD002086.pub2
Garrido-Mesa N, Zarzuelo A, Gálvez J. Minocycline: far beyond an antibiotic. British Journal of Pharmacology. 2013;169(2):337-352. doi:https://doi.org/10.1111/bph.12139
Husain MI, Chaudhry IB, Husain N, et al. Minocycline as an adjunct for treatment-resistant depressive symptoms: A pilot randomised placebo-controlled trial. Journal of Psychopharmacology. 2017;31(9):1166-1175. doi:10.1177/0269881117724352
Jonas M, Cunha BA. Minocycline. Therapeutic drug monitoring. 1982 1982;4(2):137-145.
Maibach H. Second-generation tetracyclines, a dermatologic overview: clinical uses and pharmacology. Cutis. Nov 1991;48(5):411-7.
Oliveira AC, Richards EM, Karas MM, Pepine CJ, Raizada MK. Would Repurposing Minocycline Alleviate Neurologic Manifestations of COVID-19? Opinion. Frontiers in Neuroscience. 2020-September-30 2020;14(997)doi:10.3389/fnins.2020.577780
Plane JM, Shen Y, Pleasure DE, Deng W. Prospects for Minocycline Neuroprotection. Archives of Neurology. 2010;67(12):1442-1448. doi:10.1001/archneurol.2010.191
Sapadin AN, Fleischmajer R. Tetracyclines: nonantibiotic properties and their clinical implications. J Am Acad Dermatol. Feb 2006;54(2):258-65. doi:10.1016/j.jaad.2005.10.004
Schmidtner AK, Slattery DA, Gläsner J, et al. Minocycline alters behavior, microglia and the gut microbiome in a trait-anxiety-dependent manner. Translational Psychiatry. 2019/09/13 2019;9(1):223. doi:10.1038/s41398-019-0556-9
Singh H, Kakkar AK, Chauhan P. Repurposing minocycline for COVID-19 management: mechanisms, opportunities, and challenges. Expert Review of Anti-infective Therapy. 2020/10/02 2020;18(10):997-1003. doi:10.1080/14787210.2020.1782190
Zhou Y-Q, Liu D-Q, Chen S-P, et al. Minocycline as a promising therapeutic strategy for chronic pain. Pharmacological Research. 2018/08/01/ 2018;134:305-310. doi:https://doi.org/10.1016/j.phrs.2018.07.002
Kate Byrd, PharmD, is a highly accomplished Medical Writer with a strong background in pharmacy and an unwavering commitment to producing accurate, informative content. After earning her Doctor of Pharmacy degree, Kate embarked on her career as a Medical Writer, where she has since gained valuable experience in developing evidence-based content that translates complex medical information into easy-to-understand articles. We are thrilled to announce that Kate is now bringing her expertise and dedication to the medical writing team at Pharmacists.org. Her passion for empowering readers with reliable and accessible health information aligns perfectly with our mission, making her a valuable addition to our team.