Buy Viraday may reduce the effectiveness of methadone, possibly causing symptoms of opiate withdrawal. Patients taking Viraday with carbamazepine, phenobarbitol, or phenytoin must have their anticonvulsant levels regularly monitored. Viraday may worsen the adverse effects of psychoactive drugs on the nervous system. Viraday may inhibit the functionality of ethinyl estradiol, which plays a vital role in many contraceptives.