Megestrol acetate products, method of manufacture, and method of use
View Patent ↗Disclosed herein is a method of using megestrol acetate. In one embodiment, the method comprises informing a user that megestrol acetate is metabolized by a cytochrome p450 isozyme. In another embodiment, the method comprises obtaining megestrol acetate from a container associated with published material providing information is metabolized by a cytochrome p450 isozyme. Also disclosed are articles of manufacture comprising a container containing a dosage form of megestrol acetate, wherein the container is associated with published material informing that megestrol acetate is metabolized by a cytochrome p450 isozyme, a method of treatment, and a method of manufacturing a megestrol acetate product.
1. A method of administering megestrol acetate, comprising
administering megestrol acetate to a patient in need of megestrol acetate therapy;
determining that a substance that is an inhibitor or an inducer of CYP3A4 is coadministered to the patient;
monitoring the patient's plasma concentration of megestrol acetate;
determining that the patient experiences an adverse reaction associated with elevated or decreased megestrol acetate plasma concentration during coadministration of megestrol acetate and the substance; and
adjusting administration of megestrol acetate or the substance to the patient to reduce severity of or eliminate the adverse reaction.
2. The method of claim 1 , wherein the substance is an inhibitor of CYP3A4, the patient experiences an adverse reaction associated with elevated megestrol acetate plasma concentration, and adjusting administration comprises
ceasing to administer the inhibitor or megestrol acetate.
3. The method of claim 1 , wherein the substance is an inducer of CYP3A4, the patient experiences an adverse reaction associated with reduced megestrol acetate plasma concentration, and adjusting administration comprises
ceasing to administer the inducer; or
increasing the dosage of megestrol acetate.
4. A method of avoiding an adverse event when administering megestrol acetate, comprising
determining that a patient in need of megestrol acetate therapy is taking a substance that is a known inhibitor or a known inducer of CYP3A4;
monitoring the patient's plasma concentration of megestrol acetate; and
adjusting administration to the patient of megestrol acetate or the substance to avoid an adverse event associated with a change in the metabolism of megestrol acetate,
wherein the adjusting administration comprises ceasing to administer the substance if the substance is an inducer of CYP3A4 or increasing the dosage of megestrol acetate if the substance is an inhibitor of CYP3A4.
5. The method of claim 4 , wherein the substance which is a known inhibitor of CYP3A4 is delavirdine, indinavir, nelfinavir, ritonavir, amiodarone, aprepitant, cinchloramphenicol, cimetidine, clarithromycin, diethyl-dithiocarbamate, diltiazem, erythromycin, fluconazole, fluvoxamine, gestodene, grapefruit juice, Seville orange juice, imatinib, itraconazole, ketoconazole, mifepristone, nefazodone, norfloxacin, norfluoxetine, mibefradil, star fruit, verapamil, or voriconazole.
6. The method of claim 4 , wherein the substance which is a known inducer of CYP3A4 is barbiturates, carbamazepine, efavirenz, glucocorticoids, modafinil, nevirapine, phenobarbital, phenyloin, rifampin, St. John's wort, troglitazone, oxcarbazepine, pioglitazone, or rifabutin.