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Can I take 0.18mg and Chlorpheniramine together?

Drug interaction guide

Taking these two medicines together can make you feel very sleepy, dizzy, and confused. It can also cause a very dry mouth, blurred vision, and difficulty passing urine. In some cases, it may lead to severe drowsiness that makes everyday tasks dangerous.

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Why this happens

Both medicines affect the central nervous system and have 'anticholinergic' effects. When taken together, their sedating and drying effects add up, making the side effects much stronger than if you took either medicine alone.

You should speak to your doctor before taking these two medicines together. If your doctor confirms you can take both, do not drive or operate machinery, as your coordination and reaction times will be significantly slowed. Avoid alcohol completely, as it will make the sleepiness much worse.

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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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