Can I take Venlafaxine and Viagra connect together?
Drug interaction guide
Originally published 25 Jan 2026
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Taking venlafaxine and Viagra Connect (sildenafil) together may increase the risk of side effects like dizziness, lightheadedness, or fainting. There is also a small risk of a rare but serious condition called priapism (a painful erection that will not go away).
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Why this happens
Both drugs can lower blood pressure. Venlafaxine can sometimes cause a drop in blood pressure when you stand up, and sildenafil widens blood vessels, which also lowers pressure. Combining them can make this effect stronger. Additionally, venlafaxine may slightly increase the levels of sildenafil in your blood by slowing down how your liver processes it.
What you should do
You should use this combination with caution. When starting Viagra Connect, be careful when moving from a sitting or lying position to standing, as you may feel dizzy. If you experience a painful erection or one that lasts longer than 4 hours, seek emergency medical help immediately. It is a good idea to inform your GP that you are taking both.
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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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