Drug interactions
Benzphetamine + Calcium
Severity: Minor
Benzphetamine and Calcium: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Calcium carbonate can make urine more alkaline, which reduces renal elimination of weakly basic amines such as benzphetamine. This may prolong and intensify stimulant effects such as tachycardia, hypertension and insomnia.
What this interaction means in plain words
Benzphetamine and Calcium have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Urinary alkalinization increases the un-ionized fraction of the basic drug, enhancing tubular reabsorption.
What to do
Monitor heart rate and blood pressure when large or regular doses of calcium antacids are used, and reduce the benzphetamine dose if stimulant effects increase.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
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Other interactions of Calcium
- Calcium + Ceftriaxone Contraindicated
- Acalabrutinib + Calcium Moderate
- Alendronate + Calcium Moderate
- Atazanavir + Calcium Moderate
- Baloxavir marboxil + Calcium Moderate
- Bendroflumethiazide + Calcium Moderate
Frequently asked questions
Can I take Benzphetamine with Calcium?
MediHelp rates the interaction as minor. Benzphetamine and Calcium have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Calcium carbonate can make urine more alkaline, which reduces renal elimination of weakly basic amines such as benzphetamine. This may prolong and intensify stimulant effects such as tachycardia, hypertension and insomnia.
How serious is the interaction between Benzphetamine and Calcium?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor heart rate and blood pressure when large or regular doses of calcium antacids are used, and reduce the benzphetamine dose if stimulant effects increase.
What other medicines interact with Calcium?
MediHelp also lists interactions of Calcium with, for example, Ceftriaxone, Acalabrutinib, Alendronate. The full list is on the Calcium page.
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