Minocycline (Minocin) is an anti-inflammatory antibiotic sometimes used to treat mild rheumatoid arthritis (RA). Minocycline belongs to the group of antibiotics called tetracycline. Tetracyclines are typically used to treat infections. Although RA is not thought to be caused by an infection, minocycline may improve the signs and symptoms of this disease. Because it has been studied less and may be less effective than other options, it is not commonly prescribed for RA.
Minocycline is usually taken twice a day as a 100 mg capsule. It may be taken with food but should not be taken with other medications such as antacids or iron tablets. It has a slow onset and may take several months to work.
The most common side effects from this medicine are gastrointestinal upset, dizziness, and skin rash. Patients who take this medication for a long time may notice changes in their skin color, but this usually resolves after stopping the medication. Some women who take minocycline develop vaginal yeast infections. Minocycline may increase sensitivity to sunlight, resulting in more frequent sunburns or the development of rashes following sun exposure. Sunscreen use and avoiding prolonged sun exposure and sunscreen is recommended.
Rarely, minocycline can affect the kidneys or liver. For long-term users of minocycline, doctors may recommend periodic blood tests to check liver and kidney function. In equally rare cases, minocycline can cause drug-induced lupus or similar autoimmune connective tissue disease. This condition usually resolves after stopping the medication.
Minocycline is passed into breast milk. In order to prevent delayed development of teeth and bones in their infants, mothers should avoid breast-feeding while taking minocycline. . Minocycline can also increase a nursing infant’s risk of fungal infections or dizziness. Because minocycline may cause discoloration of teeth and problems with bone growth , it is recommended that children younger than eight years old not take this medication. These side effects do not occur in older children and adults.
Talk to your rheumatology provider if you become pregnant, are planning to become pregnant, or if you are breastfeeding. Minocycline should not be given during pregnancy or used when breastfeeding. If you've had allergic reactions to minocycline or other tetracycline antibiotics, let your rheumatology provider know. Be sure to tell your rheumatology provider about all of the medications you are taking, including over-the-counter drugs and natural remedies. Possible interactions with minocycline may occur when taking warfarin (Coumadin); antacids containing calcium, aluminum, or magnesium (such as Tums, Rolaids, Maalox, or Mylanta); iron tablets; oral contraceptives (birth control pills); tretinion (“retinoids”); Accutane; Soriatane; and methotrexate.
Updated February 2022 by Nina Washington, MD, and reviewed by the American College of Rheumatology Committee on Communications and Marketing.
This patient fact sheet is provided for general education only. Individuals should consult a qualified health care provider for professional medical advice, diagnosis and treatment of a medical or health condition.