Benzphetamine and Omeprazole: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 2, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Benzphetamine
No brand names on recordOmeprazole
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
Here's what's going on. Benzphetamine is an amphetamine-type stimulant used for weight loss. Your body clears it out through your urine, and how fast that happens depends on how acidic or alkaline your urine is. Omeprazole and other stomach acid reducers can make your urine more alkaline, which can slow down how quickly the benzphetamine leaves your body.
That means the stimulant could build up and hit harder, with more side effects like a racing heart, jitteriness, trouble sleeping, or higher blood pressure. This concern is based on how the drugs work in theory, not strong studies. Please don't stop either medicine on your own. Just let your pharmacist or doctor know you take both so they can guide you.
Mechanism: Amphetamine renal elimination is pH dependent. Omeprazole can raise urinary pH, reducing renal clearance of benzphetamine's amphetamine metabolites and increasing half-life, systemic exposure, and pharmacodynamic effect.
- Direction: Increased amphetamine exposure and potentiated sympathomimetic effect.
- Evidence: Theoretical; magnitude not quantified.
- Onset: Unspecified.
- Severity on file: Major.
Management: The database advises avoiding concomitant use. If both are needed, monitor for amphetamine toxicity (tachycardia, hypertension, agitation, insomnia). Benzphetamine dosing may need to be individualized by the care team, with closer clinical monitoring. Consider whether the acid-suppression indication can be met by an alternative.
What happens
Increased exposure to amphetamine
Interaction Deep Dive
Amphetamines should not be taken together with gastrointestinal1 or urinary alkalizing agents, since doing so can raise amphetamine blood concentrations and enhance its effects 2. Because amphetamine elimination depends on pH, alkalization of the urine will markedly prolong its half-life 1.
Why it happens (mechanism)
Decreased renal elimination
How to manage this interaction
What your care team may do:
- Review whether both medicines are truly needed at the same time, since guidance is to avoid combining amphetamines with agents that alkalinize the urine.
- Watch you more closely for signs the stimulant is building up (fast heartbeat, high blood pressure, restlessness, or poor sleep).
- Individualize your benzphetamine dose or consider a different stomach medicine if appropriate.
What you can do: Keep taking both exactly as prescribed for now, and bring this up with your pharmacist or prescriber. Tell them if you notice new jitteriness, a pounding heart, or trouble sleeping.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Benzphetamine and Omeprazole together?
Omeprazole can slow how fast benzphetamine leaves your body, potentially strengthening its stimulant effects and side effects. Don't change anything on your own, but flag this combination to your pharmacist or doctor so they can adjust and monitor. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Benzphetamine and Omeprazole interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Benzphetamine and Omeprazole interaction managed?
What your care team may do: Review whether both medicines are truly needed at the same time, since guidance is to avoid combining amphetamines with agents that alkalinize the urine. Watch you more closely for signs the stimulant is building up (fast heartbeat, high blood pressure, restlessness, or poor sleep). Individualize your benzphetamine dose or consider a different stomach medicine if approp… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Benzphetamine or Omeprazole need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (2)
- Product Information: Desoxyn(R) oral tablets, methamphetamine HCl oral tablets. Recordati Rare Diseases Inc (per FDA), Lebanon, NJ, 2017.
- Product Information: EVEKEO ODT(TM) orally disintegrating tablets, amphetamine sulfate orally disintegrating tablets. Arbor Pharmaceuticals LLC (per FDA), Atlanta, GA, 2019.
Keep reading about Benzphetamine
Keep reading about Omeprazole
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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