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Can I take Doxazosin and Soft together?

Drug interaction guide

Taking doxazosin and sildenafil (Viagra) together can cause your blood pressure to drop too low. This can make you feel dizzy, light-headed, faint, or cause you to fall over.

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Why this happens

Both medicines work by relaxing and widening your blood vessels. Doxazosin is an alpha-blocker used for high blood pressure or prostate issues, while sildenafil is used for erectile dysfunction. When used together, their effects add up, which can lead to a significant and potentially dangerous drop in blood pressure.

What you should do

You should speak to your doctor before using these two medicines together. If your doctor confirms it is safe for you, they may suggest starting with the lowest possible dose of sildenafil. To reduce the risk of dizziness, make sure you are on a stable dose of doxazosin first, and always get up slowly from a sitting or lying position. If you feel very dizzy or faint, lie down immediately.

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Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.

Disclaimer

This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.

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Article history

The information on this page is written and peer reviewed by qualified clinicians.

  • 25 Jan 2026 | Originally published
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