Drug Interaction Report

MONITOR: Coadministration of turmeric with antidiabetic drugs might potentiate the risk of hypoglycemia. Some small studies have shown that curcumin, the main component in turmeric, can reduce the blood levels of glucose and/or glycosylated hemoglobin (HbA1c) in diabetic patients. In a pharmacokinetic study involving eight type-2 diabetic patients, curcumin (475 mg daily) also increased glyburide (5 mg daily) blood levels by 12% at 2 hours after glyburide administration. The combination of glyburide and curcumin significantly decreased plasma glucose levels for up to 24 hours compared to glyburide alone. However, no patient experienced hypoglycemia.

MANAGEMENT: Caution is recommended if turmeric is coadministered with antidiabetic drugs. Blood glucose should be monitored, and patients should be educated on the potential signs and symptoms of hypoglycemia (e.g., headache, dizziness, drowsiness, nervousness, confusion, tremor, hunger, weakness, perspiration, palpitation, and tachycardia) and appropriate remedial actions to take if it occurs. Patients should also be advised to take precautions to avoid hypoglycemia while driving or operating hazardous machinery.

ADJUST DOSING INTERVAL: Exenatide slows gastric emptying and may reduce the extent and rate of absorption of concomitantly administered oral medications. When acetaminophen 1000 mg was administered simultaneously with exenatide 10 mcg and also one hour, 2 hours, and 4 hours after exenatide injection, acetaminophen systemic exposure (AUC) was decreased by 21%, 23%, 24%, and 14%, respectively; peak plasma concentration (Cmax) was decreased by 37%, 56%, 54%, and 41%, respectively; and time to peak plasma concentration (Tmax) was increased from 0.6 hours in the control period to 0.9 hours, 4.2 hours, 3.3 hours, and 1.6 hours, respectively. These values were not significantly changed when acetaminophen was given one hour before exenatide injection.

MANAGEMENT: Concomitantly administered oral medications that are dependent on threshold concentrations for efficacy (e.g., antibiotics, contraceptives) or that require rapid gastrointestinal absorption (e.g., hypnotics, pain medications) should be administered at least 1 hour before exenatide. If such medications are to be administered with food, patients should be advised to take them with a meal or snack when exenatide is not administered.