Foods and Beverages Affecting Amphetamine Bioavailability
No food or beverage has been shown to reliably increase the extent of amphetamine absorption in a way that would be expected to enhance clinical efficacy. [1], [2], [3] Some foods mainly delay absorption (change time to peak). [2], [3] Certain urine-acidifying agents can reduce amphetamine exposure by increasing renal excretion. [4]
Medication- and Formulation-Specific Effects
- Lisdexamfetamine: Neither food (including a high-fat meal or yogurt) nor orange juice affects observed AUC or Cmax of dextroamphetamine after a single dose in healthy adults. [1]
- Mixed amphetamine salts / amphetamine sulfate–type products: Food does not affect the extent of absorption but prolongs Tmax for amphetamine exposures in labeled studies of extended-release formulations. [2], [3]
Evidence That “Enhancing” Foods Are Not Established
- In healthy adults given lisdexamfetamine, orange juice and food did not change AUC or Cmax, which indicates no enhancement of overall systemic exposure from these beverages/foods. [1]
- In labeled studies of amphetamine extended-release formulations, food did not change the extent of absorption, which indicates no enhancement of systemic exposure from eating. [2], [3]
Foods and Beverages That Can Reduce Amphetamine Exposure
- Ascorbic acid (vitamin C): Ascorbic acid can acidify urine and increase renal excretion of amphetamine, which lowers serum concentrations. [4]
Practical Intake-Consistency Considerations
- High-fat meals: These mainly delay absorption for certain extended-release amphetamine formulations without changing extent of absorption. [2], [3]
- Orange juice: For lisdexamfetamine, orange juice does not affect AUC or Cmax, so it is not expected to enhance efficacy. [1]
Common Pitfalls to Avoid
- Using vitamin C/ascorbic-acid supplementation to “boost” stimulant effect is contraindicated by pharmacokinetic data showing reduced amphetamine serum concentrations from urine acidification. [4]
- Assuming that acidic beverages will increase absorption is not supported for lisdexamfetamine, where orange juice does not affect AUC or Cmax. [1]
Targets and Goals of Therapy
Clinical goals for amphetamine therapy depend on symptom control and tolerability rather than maximizing absorption through diet, because available data support that dietary changes generally do not increase extent of exposure and some agents (ascorbic acid) may decrease exposure. [1], [4]