The Effect of Oxytetracycline and Doxycycline on Protein Metabolism

Oxytetracycline and doxycycline (Vibramycin) were given to patients with absent or minimal renal function. Oxytetracycline accumulated to toxic levels when used in conventional or reduced dosage. Doxycycline did not accumulate to toxic levels when given in the usual dose. Urea production showed a mean increase of 30% following administration of oxytetracycline. In some patients the increase was almost 100%. There was a 12% increase in urea production during doxycycline administration. Doxycycline has the same fundamental effect on protein synthesis as do the other tetracyclines. However, even in anuric patients the blood levels do not rise, and thus this effect is minimized. Doxycycline can be administered to patients with renal failure, but other tetracyclines should be used in renal failure only if blood levels can be monitored.