Does concomitant ingestion of a doughnut with dexamfetamine (Amfexa) significantly alter its gastrointestinal absorption and systemic exposure? | Rounds Does concomitant ingestion of a doughnut with dexamfetamine (Amfexa) significantly alter its gastrointestinal absorption and systemic exposure? | Rounds

Does concomitant ingestion of a doughnut with dexamfetamine (Amfexa) significantly alter its gastrointestinal absorption and systemic exposure?

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Last updated: May 16, 2026 · View editorial policy

Dexamfetamine (Amfexa) Food-Effect on Gastrointestinal Absorption and Exposure

Concomitant ingestion of food with Amfexa (dexamfetamine sulfate) has not been studied in a way that quantifies absorption or systemic exposure changes. The product information states that the effect of food on absorption has not been studied, so a possible effect cannot be excluded. Amfexa SmPC (professional information)

Evidence Regarding Food Timing and Exposure

Amfexa tablets are rapidly absorbed from the gastrointestinal tract. Amfexa SmPC (professional information)

The same source specifies that because food-effect data are not available, dosing should be done in a standardized manner relative to meal timing. Amfexa SmPC (professional information)

Clinical Interpretation for “Doughnut” Ingestion

A doughnut is a food, but no specific study data are available for doughnuts or for the magnitude of change in dexamfetamine AUC/Cmax when taken with such a meal. Therefore, a significant alteration cannot be confirmed and is also not excluded based on Amfexa’s labeled evidence. Amfexa SmPC (professional information)

Practical Recommendation From the Product Information

Amfexa should be taken in a standardized manner with respect to meal timing, with doses given at the same times relative to meals each day, preferably with or immediately after meals. Amfexa SmPC (professional information)

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