Adult Initially 200 mg then 100 mg every 12 hr. Childn >8 yr Initially 4 mg/kg then 2 mg/kg every 12 hr. Gonorrhea in penicillin-sensitive patients Initially 200 mg then 100 mg every 12 hr. Min of 4 days w/ 2-3 days post-therapy culture. Meningococcal carrier 100 mg 12 hrly for 5 days. Mycobacterium marinuminfections 100 mg twice daily for 6-8 wk. Uncomplicated gonococcal urethritis in male 100 mg twice daily for 5 days. Duration of treatment: Syphilis 10-15 days.
Use in patient w/ kidney failure & neonate may cause enamel hypoplasia; discoloration of teeth during tooth growth stage. Discontinue in case of superinfection. Periodically monitor organ systems during long-term use.
Hypersensitivity reactions; GI & CNS effects; maculopapular rash, erythema, skin & mucous membrane pigmentation; hemolytic anemia, thrombocytopenia, neutropenia, eosinophilia; pseudo-cerebral tumor in adults, bulging fontanels in infants, headache.
Tetracycline enhance methoxyflurane-induced nephrotoxicity. Inhibition in digestive tract w/ Na bicarbonate. Inhibition of oral absorption w/ antacids containing divalent & trivalent cations & Fe prep. Interferes w/ penicillins. Reduced plasma prothrombin activity of vit K.