Description: Seizure medicines can affect the way the body handles antibiotics. But the reverse is also true: some antibiotics affect levels of seizure medicines. If you are taking doxycycline (Vibramycin) for anthrax exposure or any other purpose and you also take carbamazepine (Tegretol, Carbatrol), your doctor should be aware that doxycycline may lower the level of carbamazepine in your blood and possibly make seizures more likely.