Simethicone–Amfexa (Immediate-Release Dextroamphetamine) Concomitant Administration
Concomitant administration of simethicone is not expected to alter the pharmacokinetics, efficacy, or safety of immediate-release dextroamphetamine (Amfexa). This expectation is supported by simethicone being an inert, minimally absorbed anti-gas agent with no clinically important drug interactions described for simethicone. [1]
Pharmacokinetic Considerations
Dextroamphetamine (including immediate-release products) is expected to be affected primarily by agents that change gastrointestinal acidity/urinary pH, which alter absorption and urinary excretion. Amfexa prescribing information (Adcock)
Simethicone is not a gastrointestinal acidifying or alkalinizing agent. Therefore, simethicone is not expected to meaningfully change dextroamphetamine absorption or urinary excretion. [1]
Efficacy Impact
No interaction affecting dextroamphetamine therapeutic effect is described with simethicone. This is consistent with the absence of simethicone in the listed medication interaction categories in Amfexa prescribing information. Amfexa prescribing information (Adcock)
Safety Impact
No safety interaction between simethicone and dextroamphetamine is described for either agent. This is consistent with simethicone having no significant drug interactions reported in standard references. [1]
Medication-Label Interaction Checks for Amfexa
Amfexa prescribing information lists interaction concerns related to:
- MAO-inhibitors (contraindicated) Amfexa prescribing information (Adcock)
- Drugs that lower amfetamine blood levels via gastrointestinal acidifying effects Amfexa prescribing information (Adcock)
- Drugs that increase amfetamine blood levels via gastrointestinal alkalinizing effects Amfexa prescribing information (Adcock)
- Other drug-class-specific effects (e.g., clonidine, antihistamines, beta-blockers) Amfexa prescribing information (Adcock)
Simethicone is not identified in these interaction sections, and no specific contraindication or precaution is stated for simethicone. Amfexa prescribing information (Adcock)