Drug interactions
Penbutolol + Tolvaptan
Severity: Minor
Penbutolol and Tolvaptan: 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
Beta-blockers can modestly raise serum potassium by impairing cellular uptake, and tolvaptan may also increase potassium. The additive effect is typically small but may matter in renal impairment.
What this interaction means in plain words
Penbutolol and Tolvaptan 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
Beta-blockade reduces cellular potassium uptake, adding to the potassium rise seen with tolvaptan.
What to do
Monitor serum potassium periodically, particularly in patients with renal impairment or on other potassium-raising drugs.
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 Tolvaptan
- Atazanavir + Tolvaptan Contraindicated
- Ceritinib + Tolvaptan Contraindicated
- Cobicistat + Tolvaptan Contraindicated
- Conivaptan + Tolvaptan Contraindicated
- Darunavir + Tolvaptan Contraindicated
- Idelalisib + Tolvaptan Contraindicated
Frequently asked questions
Can I take Penbutolol with Tolvaptan?
MediHelp rates the interaction as minor. Penbutolol and Tolvaptan have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Beta-blockers can modestly raise serum potassium by impairing cellular uptake, and tolvaptan may also increase potassium. The additive effect is typically small but may matter in renal impairment.
How serious is the interaction between Penbutolol and Tolvaptan?
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 serum potassium periodically, particularly in patients with renal impairment or on other potassium-raising drugs.
What other medicines interact with Tolvaptan?
MediHelp also lists interactions of Tolvaptan with, for example, Atazanavir, Ceritinib, Cobicistat. The full list is on the Tolvaptan page.
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