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Can I take 0.35mg and Chlorpheniramine together?

Drug interaction guide

Taking these two medicines together can make you feel extremely sleepy, dizzy, and clumsy. It can also cause significant breathing difficulties (slow or shallow breathing) and may lead to a dangerous level of sedation or unconsciousness.

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Why this happens

Both medicines act as 'depressants' on the central nervous system. When taken together, their effects add up (a synergistic effect), significantly increasing the impact on your brain's ability to control alertness and breathing.

You should not take these two medicines together unless specifically instructed and monitored by your doctor. If you are prescribed both, do not drive, operate machinery, or drink any alcohol. Seek medical help immediately if you experience extreme drowsiness, confusion, or difficulty breathing.

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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.

Article history

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

  • 14 Mar 2026 | Originally published
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