Minocycline dosage

Oral tetracyclines that probably act as anti-inflammatory and marked immunodepressing agents. Dosages currently used are 250 mg twice daily for oxytetracycline 100 mg twice daily for minocycline 100 mg once daily for doxycycline and 400 mg for lymecycline. Therapy should be prolonged for 20 days [9]... 

Hepatic function impairment Doses more than 2 g/day IV can be extremely dangerous. In the presence of renal dysfunction, and particularly in pregnancy, IV tetracycline more than 2 g/day has been associated with death secondary to liver failure. Hepatotoxicity has been reported with minocycline. Administer with caution reduce the recommended dosage and/or extend the dosing interval. 

The oral dosage for rapidly excreted tetracyclines, equivalent to tetracycline hydrochloride, is 0.25-0.5 g four times daily for adults and 20-40 mg/kg/d for children (8 years of age and older). For severe systemic infections, the higher dosage is indicated, at least for the first few days. The daily dose is 600 mg for demeclocycline or methacycline, 100 mg once or twice daily for doxycycline, and 100 mg twice daily for minocycline. Doxycycline is the oral tetracycline of choice because it can be given as a once-daily dose and its absorption is not significantly affected by food. All tetracyclines chelate with metals, and none should be orally administered with milk, antacids, or ferrous sulfate. To avoid deposition in growing bones or teeth, tetracyclines should be avoided in pregnant women and children less than 8 years of age. 

Dizziness, vertigo, nausea, and vomiting have been noted particularly with doxycycline at doses above 100 mg. With dosages of 200-400 mg/d of minocycline, 35-70% of patients will have these reactions. 

The three tetracyclines most recently marketed were made by a semisynthetic pathway. The first of these were methacycline (6-methylene oxytetracycline) (5), C22H22N2OS. and its reduction product doxycycline (6). C22H24CIN2O2- The latter compound is a potent antibiotic which is well-absorbed and slowly excreted, thus allowing small and infrequent (once or twice a day) dosage schedules. Finally, the most recent addition to the commercial tetracyclines is minocycline (7). C21H27N3O7. which is also well-absorbed and slowly excreted. 

Tetracycline and its derivative, minocycline, are used for control of acne vulgaris. Conjunctival deposits similar to those seen in epinephrine-treated glaucoma patients have been observed in patients treated orally with these compounds. Dosages ranged from 250 to 1,500 mg daily of tetracycline and at least 100 mg daily of minocycline. 

Clarithromycin (0.75-2 g/day), minocycline (200 mg/ day), and clofazimine (100 mg/day) for 15 months were investigated as treatment of MAC lung disease in 30 HIVnegative patients. Eight patients did not complete the study owing to deviations from protocol or adverse effects. Persistently negative cultures were found in 14 of the other patients. There were three cases of hepatic disturbances and three of ototoxicity, which required a reduction in clarithromycin dosage after a short interruption of treatment (10). 

A 70-year-old man with hypertension took nifedipine 10 mg bd and 3 months later developed a pruritic eruption on his back, which spread to cover his trunk, limbs, face, and scalp, with involvement of the mouth. His skin deteriorated after the dosage of nifedipine was increased to 20 mg bd 1 year later. Antibodies to the 230 kDa pemphigoid antigen were detected in his serum. His skin improved considerably after withdrawal of nifedipine and the use of topical steroids and oral minocycline. 

ROUTES OF ADMINISTRATION AND DOSAGE A variety of tetracyclines are available for oral, parenteral, and topical administration. Tetracycline, oxytetracycline (TERRAMYCIN, others), demeclocycline (declomycin), minocycline (minocin, others), and doxycycline (vibramycin, others) are available in the U.S. 

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