Praziquantel and Food

Food can enhance the levels of praziquantel in your body. To ensure maximal oral absorption, praziquantel should be administered with or immediately after a meal. This will make it easier for your body to absorb the medication. If you are receiving therapy with praziquantel you should avoid grapefruits and grapefruit juice. Grapefruit can raise the levels of praziquantel in your body and increase side effects of dizziness, abdominal discomfort, and nausea.. Do not increase or decrease the amount of grapefruit products in your diet without first talking to your doctor.

ADJUST DOSING INTERVAL: Administration with food increases the oral bioavailability of praziquantel. The mechanism has not been described. In nine healthy volunteers, administration of praziquantel (1800 mg single oral dose) following a high-fat meal increased the mean praziquantel peak plasma concentration (Cmax) and area under the concentration-time curve (AUC) by 243% and 180%, respectively, compared to administration under fasting conditions. Administration with a high-carbohydrate meal increased these values by 515% and 271%, respectively, compared to fasting. Overall, the relative bioavailability was increased by a factor of 2.72 and 3.98 with the high-fat and high-carbohydrate meals, respectively. The time to reach peak concentration (Tmax) and elimination half-life (T1/2) were not significantly altered.

Coadministration with grapefruit juice may increase the oral bioavailability of praziquantel. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall induced by certain compounds present in grapefruits. In 18 healthy volunteers, administration of praziquantel (1800 mg single oral dose) with 250 mL of commercially squeezed grapefruit juice resulted in decreases in the mean praziquantel Cmax and AUC of 63% and 90%, respectively, compared to administration with water. The Tmax and T1/2 were not significantly altered. The pharmacokinetics of praziquantel were subject to a high degree of interpatient variability with and without grapefruit juice.

MANAGEMENT: To ensure maximal oral absorption, praziquantel should be administered with meals. Administration with grapefruit juice may further increase pharmacologic effects of praziquantel, including adverse effects such dizziness, abdominal discomfort, and nausea.