Tri-monocycline: a minocycline complex for parenteral use. II. Blood levels, tissue contents and excretion of the antibiotic in animal experiments and after intravenous administration to humans.

Tri-minocycline prepared by mere dissolution of minocycline in an aqueous solution of a recommended complexing agent or using a preconstituted ready-for-use injection of the complex was administered intravenously to rabbits. Serum values were lower, tissue values higher than after injection of other tri-tetracyclines. Basing on these experimental quantitative data, single doses of tri-minocycline equivalent to 50-150 mg minocycline hydrochloride were administered once or twice daily to 13 adult patients during 1-6 days intravenously, without any serious or unusual side-effects. On average, 12% of the injected antibiotic was excreted in the urine, not later than 96 h after the last dose.