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Can I take 15 and Guanfacine prolonged-release together?

Drug interaction guide

Drinking alcohol while taking guanfacine can make you feel very sleepy, dizzy, or lightheaded. It can also cause your blood pressure or heart rate to drop to unsafe levels.

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Why this happens

Both alcohol and guanfacine have a 'depressant' effect on the central nervous system and can lower blood pressure. When used together, these effects are added together (additive effect), making them much stronger than usual.

It is best to avoid or strictly limit alcohol while taking guanfacine. Do not drive or operate machinery if you feel drowsy or dizzy. If you feel faint or your heart feels like it is beating very slowly, contact your doctor immediately.

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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.

  • 14 Mar 2026 | Originally published
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