Content reviewed by the PillRelax Healthcare Team | Last reviewed: September 2026
Like all medicines, Zopiclone can cause side effects. Understanding what to expect helps you use it safely.
Very Common Side Effects (more than 1 in 10)
- Bitter or metallic taste – the most distinctive side effect. Drinking water or brushing teeth helps.
- Dry mouth
Common Side Effects (1 in 10 to 1 in 100)
- Daytime drowsiness or sedation
- Dizziness and headache
- Nausea
- Coordination problems
Rare but Serious Side Effects – Seek Medical Advice
- Sleepwalking and complex sleep behaviours – including sleep-eating and sleep-driving
- Paradoxical reactions – increased anxiety, agitation (more common in elderly)
- Severe allergic reaction – rash, difficulty breathing, facial swelling
Managing Common Side Effects
Metallic taste: chewing sugar-free gum on waking helps. Daytime drowsiness: ensure you get a full 7-8 hours of sleep after taking Zopiclone.
When to Stop and Seek Help
Stop Zopiclone and seek medical advice if you experience sleepwalking, significant memory problems, severe confusion, or signs of an allergic reaction.
Frequently Asked Questions
Does Zopiclone cause weight gain?
Weight gain is not a commonly reported side effect. Disrupted sleep itself can affect metabolism and appetite.
Is the bitter taste permanent?
No. It is temporary and related to Zopiclone’s excretion in saliva. It resolves once the medicine clears your system.
