humatrope and Aromasin Interactions

Interactions between humatrope(somatropin) and Aromasin (exemestane)

somatropin and exemestane (Moderate Drug-Drug)

ADJUST DOSE: Coadministration with potent inducers of CYP450 3A4 may significantly decrease the plasma concentrations of exemestane, which is primarily metabolized by the isoenzyme. In 10 healthy postmenopausal volunteers, administration of exemestane (25 mg single dose) following pretreatment with the potent inducer rifampin (600 mg daily for 14 days) resulted in a 41% decrease in exemestane peak plasma concentration (Cmax) and a 54% decrease in exemestane systemic exposure (AUC).

MANAGEMENT: The manufacturer recommends increasing the dosage of exemestane to 50 mg once daily when used in combination with potent CYP450 3A4 inducers such as carbamazepine, phenobarbital, phenytoin, and rifampin. However, it has also been suggested that suppression of estrogen levels is not affected by the interaction, thus dosage adjustment of exemestane is not required. Other known inducers include aminoglutethimide, barbiturates, bexarotene, bosentan, efavirenz, etravirine, nevirapine, somatrem, somatropin, and various other anticonvulsants, although the extent to which they interact with exemestane is unknown.