What Are Z Drugs?
Z Drugs are prescription-only medicines (POM) used for significant sleep problems, like trouble falling asleep or staying asleep. They’re called “Z Drugs” because their generic names usually begin with the letter “Z”.
In the UK, the main Z Drugs are:
- Zopiclone (brand name: Zimovane®) – often prescribed for short-term insomnia.
- Zolpidem (brand name: Stilnoct®) – helps with falling asleep more quickly.
- Zaleplon (brand name: Sonata®) – previously available but no longer authorised in the UK.
Though not benzodiazepines, Z Drugs act on similar brain receptors. They’re fast-acting with shorter effects, meaning less next-day drowsiness – but they can still lead to dependence and withdrawal if used for too long.
SPN: POM = Prescription Only Medicine – you can only get these after a consultation with a healthcare professional.
When Should Z Drugs Be Prescribed?
Z Drugs should only be prescribed for severe insomnia and only after non-medication options (like sleep hygiene or CBT-I) have been tried. For older adults, doctors may prefer Z Drugs over benzodiazepines because they wear off faster and are less likely to cause heavy grogginess the next day.
When Shouldn’t They Be Prescribed?
Doctors usually avoid prescribing Z Drugs if you have:
- Serious breathing problems (e.g. advanced respiratory disease)
- Sleep apnoea
- Severe liver or kidney conditions
- Unmanaged neuromuscular illnesses like myasthenia gravis
- A history of substance misuse or certain mental health conditions (extra caution is used)
Taking Z Drugs Responsibly
If you’re prescribed a Z Drug, you should:
- Take it just before bed and on an empty stomach
- Never mix with alcohol
- Use the lowest effective dose for the shortest time possible
- Stop gradually – not suddenly – to avoid withdrawal symptoms
SPN: Most prescriptions are for a few days to 2 weeks. Long-term use is rarely recommended.
Risks and Activities While on Z Drugs
Z Drugs can cause unusual behaviours during sleep, like sleep-walking, driving, or eating without remembering it. If you notice these effects, contact your doctor immediately.
SPN: These behaviours are rare but potentially dangerous – avoid driving or operating machinery unless you’re fully awake.
Other Medicines Sometimes Used for Sleep
Antihistamines
Some sedating antihistamines are available over the counter (OTC) for short-term sleep problems. Common examples include:
- Diphenhydramine (brands like Nytol®)
- Promethazine (brands like Phenergan®)
They can make you feel groggy the next day and lose effect if used too often.
SPN: Not suitable for everyone – people with glaucoma, epilepsy, or an enlarged prostate should check with their doctor first.
Melatonin
Melatonin is a hormone your body naturally produces. In the UK, Circadin® is a prescription-only melatonin tablet for short-term use in people over 55.
Older Sedatives
Drugs like chloral hydrate, clomethiazole, and barbiturates were once common sleep aids but are now rarely used due to serious side effects and overdose risk.