α-6-Deoxyoxytetracycline III. Total and Unbound Antibiotic Serum Concentrations After Oral Administration to Mice

Summary

1. The results of mouse serum level studies are presented in terms of total and unbound antibiotic concentrations. DOOTC administered at one-half the oral dosage of MOTC, TC, and DMCT produced higher and longer lasting total and unbound drug concentrations than the latter antibiotics. 2. It is suggested that the previously reported chemotherapeutic superiority of DOOTC over these drugs results from the achievement and maintenance of superior unbound drug levels. 3. The more efficient oral absorption of DOOTC over the other tetracyclines (3.5-4.5 times) in the mouse was demonstrated by comparing cummulative urinary excretion ratios obtained after oral and intravenous drug administration.