Minocycline is indicated for oral administration for the treatment of infections caused by tetracycline-sensitive organisms and some tetracycline-resistant strains of staphylococci.

Indications include: Acne, skin and soft tissue infections, ophthalmological infections, acute and chronic bronchitis, bronchiectasis, lung abscess, ear, nose and throat infections, pelvic inflammatory disease, nocardiosis, urinary tract infections, gonorrhoea, non-gonococcal urethritis, and prostatitis. Minocycline may also be used in the prophylactic treatment of asymptomatic meningococcal carriers. It is also indicated for pre- and post-operative prophylaxis of infection.

• Routine antibiotic use: 200 mg daily in divided doses
• Acne: 50 mg twice daily for at least 6 weeks.
• Gonorrhoea: Males: 200 mg initially followed by 100 mg every 12 hours for a minimum of 4 days. Post therapy cultures within 2–3 days. Females: May require a more prolonged therapy.
• Prophylaxis of asymptomatic meningococcal carriers: 100 mg twice daily for 5 days, followed by treatment with rifampicin.

If, after six months, there is no satisfactory response minocycline should be discontinued and other therapies considered. If minocycline is to be continued for longer than six months, patients should be monitored at least three monthly intervals thereafter for signs and symptoms of hepatitis or SLE.

Anticoagulants: Plasma prothrombin activity is depressed by tetracyclines. Reduced doses of any concomitant anticoagulants may be necessary.

ACE inhibitors, antacids and adsorbents: Tetracyclines bind to di-/tri-valent cations. Absorption from the gastrointestinal tract is impaired by concomitant administration of iron, calcium, aluminium, magnesium, bismuth and zinc salts (interactions with specified salts, antacids, kaolin, bismuth-containing ulcer-healing drugs, quinapril which contains a magnesium carbonate excipient). Dosages should be maximally separated. Absorption of tetracyclines is not significantly impaired by food, milk and milk products.

Diuretics: Diuretics may aggravate nephrotoxicity by volume depletion.

Antibacterials: Minocycline should not be used with penicillins.

Ergotamine and ergometrine: There is an increased risk of ergotism.

Oral contraceptives: Both can induce hyperpigmentation.

Retinoids: Administration of isotretinoin should be avoided shortly before, during and shortly after minocycline therapy.

Minocycline is contraindicated in patients with hypersensitivity to tetracyclines, systemic lupus erythematosus, pregnancy, lactation, complete renal failure and children under 12 years.

Reported side effects include oral and anogenital candidiasis, vulvovaginitis, eosinophilia, leucopenia, neutropenia, thrombocytopenia, haemolytic anaemia, pancytopenia, agranulocytosis, anaphylaxis, anaphylactoid reaction, hypersensitivity, pulmonary infiltrates, anaphylactoid purpura, polyarteritis nodosa, abnormal thyroid function, brown-black discolouration of the thyroid, anorexia, dizziness, headache, hypaesthesia, paraesthesia, intracranial hypertension, vertigo, bulging fontanelle, convulsions, sedation, impaired hearing, tinnitus, myocarditis, pericarditis, cough, dyspnoea, bronchospasm, exacerbation of asthma, pulmonary eosinophilia, pneumonitis, diarrhoea, nausea, stomatitis, discolouration of teeth, vomiting, dyspepsia, dysphagia, enamel hypoplasia, enterocolitis, oesophagitis, oesophageal ulceration, glossitis, pancreatitis, pseudomembranous colitis, increased liver enzymes, hepatitis, autoimmune hepatotoxicity, hepatic cholestasis, hepatic failure, hyperbilirubinemia, jaundice, autoimmune hepatitis, alopecia, erythema multiforme, erythema nodosum, fixed drug eruption, hyperpigmentation of the skin, photosensitivity, pruritus, rash, urticaria, vasculitis, angioedema, exfoliative dermatitis, hyperpigmentation of nails, Stevens-Johnson syndrome, toxic epidermal necrolysis, Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS), arthralgia, lupus-like syndrome, myalgia, arthritis, bone discolouration, cases of systemic lupus erythematosus (SLE), joint stiffness, joint swelling, increased serum urea, acute renal failure, interstitial nephritis, balanitis, fever, etc. In some cases involving these syndromes, death has been reported.

Hyperpigmentation of various body sites including the skin, nails, teeth, oral mucosa, bones, thyroid, eyes (including sclera and conjunctiva), breast milk, lacrimal secretions and perspiration has been reported. This blue/black/grey or muddy-brown discolouration may be localised or diffuse. The most frequently reported site is the skin. Pigmentation is often reversible on discontinuation of the drug, although it may take several months or may persist in some cases. Generalised muddy-brown skin pigmentation may persist, particularly in sun-exposed areas.

Minocycline use during pregnancy and lactation is contraindicated. Animal studies have shown that tetracyclines cross the placenta. Tetracyclines have been found in foetal tissues and may have toxic effects on the developing foetus (including retardation of skeletal development). Studies in animals treated during early pregnancy also indicate embryotoxicity. Use during the last half of pregnancy, when teeth are developing, may cause permanent tooth discolouration (more common with long-term or repeated short-term use). Enamel hypoplasia has also been reported. Tetracyclines have been detected in the milk of lactating women. Permanent tooth discolouration and enamel hypoplasia may occur in the developing infant.

Breathing difficulties: Cases of dyspnoea, bronchospasm, exacerbation of asthma, pulmonary eosinophilia and pneumonitis have been reported. If breathing difficulties develop, patients should seek urgent medical advice and minocycline should be discontinued.

Paediatric population: All tetracyclines form a stable calcium complex in bone-forming tissue. Increased fibula growth rate has been observed in premature infants receiving oral tetracyclines. They may cause yellow to brown tooth discolouration and enamel hypoplasia in developing children or foetuses.

Hepatic impairment: Use with caution in patients with liver dysfunction or when used with potentially hepatotoxic drugs including alcohol.

Auto-immune disorders: Rare cases of autoimmune hepatotoxicity and isolated cases of systemic lupus erythematosus (SLE) have been reported. Discontinue if signs of SLE or hepatotoxicity occur.

Renal impairment: No significant drug accumulation occurs in mild to moderate renal impairment at recommended doses. In severe renal impairment, dose reduction and monitoring may be required.

Cross-sensitivities: Cross-resistance and cross-sensitivity may occur. Discontinue if signs of resistant organism overgrowth appear.

Intracranial hypertension: Bulging fontanelles in infants and benign intracranial hypertension in juveniles and adults have been reported. Symptoms include headache and visual disturbances. Permanent vision loss has been reported. Discontinue if raised intracranial pressure develops.

Hyperpigmentation: May occur at various body sites, more commonly with long-term use. Patients should report unusual pigmentation and discontinue treatment if it develops.

Photosensitivity: Patients should avoid direct sunlight or artificial UV exposure and discontinue at first sign of skin discomfort.

Renal impairment: Generally safe in mild to moderate impairment; caution in severe renal impairment.

Paediatric population: Not recommended under 12 years. Children over 12 years: 50 mg every 12 hours.

Dizziness, nausea and vomiting are the most common symptoms. Gastric lavage and supportive treatment are recommended. Antacids and calcium salts may reduce absorption. No specific antidote is available. Minocycline is not significantly removed by haemodialysis or peritoneal dialysis.

Tetracycline group of drugs

Store in a cool and dry place, protected from light. Store below 25°C.