Effect of a single oral dose of doxycycline on polymorphonuclear leukocyte migration in a casein gradient.

Tetracyclines, especially doxycycline, have been reported to inhibit the in vitro migration of polymorphonuclear leukocytes (PMNs). Twelve healthy probands were treated with doxycycline 200 mg. No inhibition of PMN migration in a casein gradient was demonstrated 24 h later. It is suggested that the effect of oral treatment with doxycycline on PMN chemotaxis is negligible.