Comparative bioavailability of tetracycline and lymecycline.

The relative bioavailability of lymecycline and tetracycline hydrochloride was compared in 12 healthy volunteers in a double-blind cross-over study using a high performance liquid chromatographic method for plasma and urine analyses. A statistical significant difference in favour of tetracycline hydrochloride was found concerning the mean AUC and the mean lag time. The relative bioavailability of lymecycline was only 70% compared with tetracycline in multiple dosing (19.13 +/- 5.39 micrograms ml-1 h and 27.22 +/- 6.26 micrograms ml-1 h respectively) and 80% in a single dose (21.88 +/- 4.23 micrograms ml-1 h and 26.91 +/- 6.01 respectively) and the mean lag time of tetracycline was only 60% compared with lymecycline.