Monas has been administered with other therapies routinely used in the prophylaxis and chronic treatment of asthma with no apparent increase in adverse reactions. In drug interaction studies, the recommended clinical dose of Monas did not have clinically important effects on the pharmacokinetics of the following drugs: theophylline, prednisone, prednisolone, oral contraceptives (norethindrone 1mg/ethinyl estradiol 35mcg), terfenadine, digoxin, and warfarin. Although additional specific interaction studies were not performed, Monas was used concomitantly with a wide range of commonly prescribed drugs in clinical studies without evidence of clinical adverse interactions. These medications included thyroid hormones, sedative hypnotics, non-steroidal anti-inflammatory agents, benzodiazepines and decongestants. Phenobarbital, which induces hepatic metabolism, decreased the AUC of Monas approximately 40% following a single 10mg dose of Monas. No dosage adjustment for Monas is recommended. It is reasonable to employ appropriate clinical monitoring when potent cytochrome P450 enzyme inducers, such as phenobarbital or rifampin, are co-administered with Monas