Drug interactions
Phenylephrine po + Terazosin
Severity: Minor
Phenylephrine po and Terazosin: 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
Oral phenylephrine is an alpha-1 agonist that may counteract terazosin, potentially raising blood pressure or reducing therapeutic effect. The effect is usually small because oral absorption of phenylephrine is limited.
What this interaction means in plain words
Phenylephrine po and Terazosin 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
Pharmacodynamic antagonism at alpha-1 adrenergic receptors.
What to do
Monitor blood pressure with regular decongestant use and prefer non-adrenergic alternatives in hypertensive patients.
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 Terazosin
- Alfuzosin + Terazosin Major
- Amifostine + Terazosin Major
- Avanafil + Terazosin Major
- Doxazosin + Terazosin Major
- Dutasteride-tamsulosin + Terazosin Major
- Lofexidine + Terazosin Major
Frequently asked questions
Can I take Phenylephrine po with Terazosin?
MediHelp rates the interaction as minor. Phenylephrine po and Terazosin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Oral phenylephrine is an alpha-1 agonist that may counteract terazosin, potentially raising blood pressure or reducing therapeutic effect. The effect is usually small because oral absorption of phenylephrine is limited.
How serious is the interaction between Phenylephrine po and Terazosin?
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 blood pressure with regular decongestant use and prefer non-adrenergic alternatives in hypertensive patients.
What other medicines interact with Terazosin?
MediHelp also lists interactions of Terazosin with, for example, Alfuzosin, Amifostine, Avanafil. The full list is on the Terazosin page.
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