Description
Zopiclone 20 mg Tablets: The Standard Adult Dose, Its Limits and What to Know About Tolerance and Driving
Zopiclone 20 mg is the highest strength of this sleeping tablet and the usual dose for healthy adults when a lower dose has not been enough. It is prescribed for short-term insomnia only. Because it is the maximum dose, it is also the strength where the risks, especially next-day drowsiness, tolerance and dependence, matter most.
This guide explains when 20 mg is used, why it must never be exceeded, how to take it safely and how to come off it. It is general education and does not replace your prescriber’s instructions.
Controlled prescription medicine. Zopiclone is a Schedule 4 (Part 1) controlled drug in the UK. It can only be supplied against a valid prescription, and supplying it to someone else is a criminal offence. We cannot supply it without a valid prescription.
Zopiclone 20 mg at a Glance
| Medicine | Zopiclone (“Z-drug” hypnotic) |
|---|---|
| Strength | 20 mg per tablet |
| Used for | Short-term treatment of insomnia in adults |
| Usual use | One tablet immediately before bed, only when you can have a full night’s sleep |
| Maximum dose | 20 mg in 24 hours; never take more or repeat the dose |
| Treatment length | As short as possible, usually no more than about four weeks including dose reduction |
| Legal status | Schedule 4 (Part 1) controlled drug |
| Prescription required | Yes |
When the 20 mg Tablet Is Used
Prescribers aim for the lowest dose that works. The 20 mg tablet is generally chosen for:
- Adults who have tried a lower dose, such as 20 mg, without enough benefit
- Adults with severe, distressing insomnia, where a short course is judged appropriate
- People who are not especially sensitive to sedatives, are not frail and do not have significant liver or kidney problems
It is generally not the starting dose for older adults or people with liver or kidney problems. For them, 20 mg is usually the ceiling or the starting point.
Why You Must Never Go Above 20 mg
20 mg is the maximum licensed dose in the . Taking more does not make the medicine work better. It increases drowsiness, confusion, memory problems and breathing risk, and overdose can be dangerous, especially with alcohol or other sedatives. Do not take a second tablet if you wake in the night, and do not take a tablet earlier or later than your prescriber advises.
Before You Rely on a Tablet
Sleeping tablets work best alongside other steps. Clinical guidance recommends trying these first or in parallel:
- A regular sleep routine, with the same bedtime and waking time daily
- A dark, cool, quiet bedroom, used only for sleep
- Less caffeine, particularly after midday, and no heavy meals or screens close to bed
- Cognitive behavioural therapy for insomnia (CBT-I), which has the best long-term results
How to Take Zopiclone 20 mg
- Take it only at bedtime, immediately before you get into bed.
- Only take it if you can stay in bed for a full night, about seven to eight hours.
- Swallow with water. Never take it with alcohol.
- Take one tablet a night at most, and only on the nights your prescriber advises.
- Do not extend your course beyond what you were prescribed.
If you wake in the night
Do not take another tablet. Wait until the following evening.
Next-Day Impairment and Driving Law
Zopiclone can leave you drowsy, slow or unsteady the following day, and the effect is greater at 7.5 mg, if you sleep for less than a full night, or if you take it with other sedating substances. In the UK:
- It is an offence to drive while impaired by a medicine, including a prescribed one.
- Zopiclone is among the medicines covered by the drug-driving law, which sets limits for certain drugs in the blood. There is a medical defence for people who take it as prescribed and are not impaired, but you cannot rely on it if you are drowsy.
- If you feel any effect in the morning, do not drive, cycle or use machinery.
Read the official guidance on the GOV.UK drug-driving page.
Tolerance, Dependence and Withdrawal
Tolerance
With regular use, the same dose can stop working as well after a few weeks. This is a sign of tolerance, not a reason to take more.
Dependence
Zopiclone acts on the same brain receptors as benzodiazepines, and it carries a similar risk of dependence, particularly when taken nightly for more than a few weeks or at the top dose. People with a history of drug or alcohol problems are at higher risk.
Rebound insomnia and withdrawal
Stopping suddenly after regular use can cause rebound insomnia (a few nights of worse sleep than before), anxiety, restlessness, sweating, tremor, nausea and, rarely, seizures or confusion. To prevent this, your prescriber will reduce the dose gradually. Do not stop abruptly if you have been taking it regularly.
If you feel unable to sleep without it, or you have been taking it longer than planned, tell your doctor. This is common and nothing to be embarrassed about, and support is available through your GP and local drug and alcohol services.
Other Risks
Complex sleep behaviours
Rarely, people have got up and done things in their sleep, such as sleepwalking, eating or driving, with no memory of it. If this happens, stop the tablets and contact your doctor straight away.
Memory problems
Some people cannot remember events after taking the tablet. Going to bed straight away reduces this.
Low mood
Sleeping tablets can sometimes worsen low mood or bring on thoughts of self-harm. If this happens, contact your doctor straight away. In an emergency call 999, or call Samaritans free on 116 123.
Breathing
Zopiclone can slow breathing, particularly with alcohol, opioids or other sedatives. If someone is very difficult to wake or breathing slowly or shallowly, call 999.
Common Side Effects
- A bitter or metallic taste, the best-known effect
- Dry mouth
- Morning drowsiness or a hangover feeling
- Dizziness or headache
- Nausea or indigestion
- Vivid dreams or nightmares
Alcohol and Other Medicines
Alcohol is the biggest risk. Combining it with zopiclone greatly increases sedation and the chance of accidents and breathing problems. Do not drink on a night you take it.
| Medicine | Concern |
|---|---|
| Opioid painkillers | Serious sedation and breathing risk |
| Benzodiazepines and other sleeping tablets | Added sedation; usually not combined |
| Pregabalin and gabapentin (see our pregabalin page) | Added drowsiness and breathing risk |
| Sedating antihistamines, antidepressants and antipsychotics | Increased drowsiness |
| Clarithromycin, erythromycin, ketoconazole, itraconazole | Can raise zopiclone levels; a lower dose may be needed |
| Rifampicin, carbamazepine, phenytoin, St John’s wort | May weaken the effect of zopiclone |
Who Should Not Take Zopiclone
- People with myasthenia gravis
- People with severe breathing problems or sleep apnoea
- People with severe liver disease
- Anyone with a past allergic reaction to zopiclone
- Anyone with a history of drug or alcohol dependence, who usually needs a different approach
- Pregnancy and breastfeeding: generally avoided. Tell your prescriber if you are pregnant, planning a pregnancy or breastfeeding.
Storage and Disposal
- Keep in the original pack at room temperature, out of sight and reach of children.
- Store securely, since zopiclone can be misused.
- Return unused tablets to a pharmacy, and never give them to anyone else.
Frequently Asked Questions
Is 20 mg the maximum dose?
Yes. Do not take more than one 20 mg tablet in 24 hours.
How long does zopiclone stay in the body?
Its effects last several hours, but it can still affect alertness the next day. Allow a full night of sleep, and do not drive if you feel any impairment.
Why has zopiclone stopped working?
This can be tolerance. Do not raise the dose. Speak to your prescriber about stopping gradually and other approaches such as CBT-I.
Can I drink alcohol with zopiclone?
No. Alcohol increases drowsiness and breathing risks.
Can I drive the day after taking zopiclone?
Only if you feel completely alert after a full night’s sleep. If you feel drowsy or slow, do not drive.
Can I stop zopiclone suddenly?
Not if you have taken it regularly. Reduce gradually with your prescriber’s guidance.
Is 20 mg safe for older adults?
Older adults are usually given 10 mg because they are more sensitive to sedatives and more likely to fall.
Can I buy zopiclone without a prescription?
No. It is a controlled drug and must be supplied on a valid prescription.
Where to Read More
See the NHS zopiclone guide, the NHS insomnia pages and the GOV.UK drug-driving law page.
Medical disclaimer: This information is for general education and does not replace advice from a qualified healthcare professional. Always follow your prescriber’s instructions and the patient leaflet supplied with your medicine.
Reviews
There are no reviews yet.