Doxivet Doxycycline Phenytoin Sodium
ModeratePhenytoin can speed up how the body breaks down doxycycline, so the doxycycline may not stay in the blood long enough to work as well. Doxycycline is one of several medicines this happens with, including HMG-CoA reductase inhibitors and TCAs (tricyclic antidepressants).
These medicines are often taken together with some care. Your doctor may change a dose, space them apart or check on you more often. Make sure your doctor and pharmacist know you take both.