Respiratory infections such as pneumonia Rocky Mountain spotted fever Rosacea Syphilis (when penicillin cannot be given) Urinary tract infections, rectal infections, and infections of the cervix caused by certain microbes Other Both minocycline and doxycycline have shown effectiveness in asthma due to immune-suppressing effects. Minocycline and doxycycline have modest effectiveness in treating rheumatoid arthritis. However, the 2015 American College of Rheumatology guideline for the treatment of rheumatoid arthritis does not include minocycline. Recent research indicate that centrally infused minocycline attenuates brain microglial activation, neuroinflammation and sympathetic activation during pulmonary hypertension Contraindications The drug is contraindicated in people with known hypersensitivity 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 pregnancy. Side effects Minocycline may cause upset stomach, diarrhea, dizziness, unsteadiness, drowsiness, mouth sores, headache, and vomiting. It increases sensitivity to sunlight, and may affect the quality of sleep and rarely causes sleep disorders. 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, yellowing of the eyes or skin, stomach pain, sore throat, vision changes, and mental changes, including depersonalization. Occasionally, minocycline therapy may result in autoimmune disorders such as drug-related lupus and autoimmune hepatitis, 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 syndrome can occur during the first few weeks of therapy with minocycline. Minocycline, but not other tetracyclines, can cause vestibular disturbances with dizziness, ataxia, vertigo, and tinnitus. These effects are thought to be related to minocycline's greater penetration into the central nervous system. Vestibular side effects are much more common in women than in men, occurring in