Drug interactions
Doxazosin + Terazosin
Severity: Major
Doxazosin and Terazosin: major 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
Doxazosin and terazosin are both alpha-1 blockers, so combining them duplicates therapy and increases the risk of marked hypotension, dizziness and syncope.
What this interaction means in plain words
Doxazosin and Terazosin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Doxazosin belongs to Genitourinary; Terazosin belongs to Genitourinary.
Why it happens
Duplicate alpha-1 adrenergic receptor blockade with additive vasodilation.
What to do
Avoid concurrent use and keep to a single alpha-blocker. When switching, stop one agent before starting the other and monitor orthostatic blood pressure.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Doxazosin
- Alfuzosin + Doxazosin Major
- Amifostine + Doxazosin Major
- Avanafil + Doxazosin Major
- Doxazosin + Dutasteride-tamsulosin Major
- Doxazosin + Phentolamine Major
- Doxazosin + Prazosin Major
Other interactions of Terazosin
- Alfuzosin + Terazosin Major
- Amifostine + Terazosin Major
- Avanafil + Terazosin Major
- Dutasteride-tamsulosin + Terazosin Major
- Lofexidine + Terazosin Major
- Phentolamine + Terazosin Major
Frequently asked questions
Can I take Doxazosin with Terazosin?
MediHelp rates the interaction as major. Doxazosin and Terazosin can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Doxazosin and terazosin are both alpha-1 blockers, so combining them duplicates therapy and increases the risk of marked hypotension, dizziness and syncope.
How serious is the interaction between Doxazosin and Terazosin?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid concurrent use and keep to a single alpha-blocker. When switching, stop one agent before starting the other and monitor orthostatic blood pressure.
What other medicines interact with Doxazosin?
MediHelp also lists interactions of Doxazosin with, for example, Alfuzosin, Amifostine, Avanafil. The full list is on the Doxazosin page.
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