Drug class · Nervous system

Z-drugs

Also known as: z-drug, non-benzodiazepine hypnotics, sleeping tablets

Z-drugs are sleeping medicines used for insomnia, and zopiclone is the member covered on this site. NICE technology appraisal TA77 covers zaleplon, zolpidem and zopiclone for short-term insomnia. The NHS describes zopiclone as a prescription-only sleeping medicine for short-term treatment of severe insomnia. MedlinePlus warns that zolpidem can cause serious, possibly life-threatening sleep behaviours, such as driving while not fully awake, without remembering it afterwards.

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Also called
z-drug, non-benzodiazepine hypnotics, sleeping tablets

Mechanism of action

The NHS says zopiclone boosts the effect of GABA, a calming chemical in the brain. A StatPearls review says zolpidem binds preferentially to one benzodiazepine receptor subtype, whereas benzodiazepines act on all subtypes. NICE says that, as with benzodiazepines, the sedative effects of the Z-drugs may persist into the next day.

Members of the class

zopiclonezolpidem

Members with a page on this site are linked.

Class effects

  • The NHS lists a dry mouth, a bitter or metallic taste, and feeling sleepy or tired the next day as common side effects of zopiclone.
  • The NHS lists sleepwalking, or doing things such as making food or phone calls while asleep, and a serious allergic reaction as possible serious side effects of zopiclone.

Cautions

  • The NHS says alcohol with zopiclone can cause very deep sleep, so that breathing is not normal and waking is very difficult.
  • The NHS advises against driving, riding a bike or using machinery for 12 hours after taking zopiclone.
  • The NHS says the body gets used to zopiclone quickly, which is why it is usually prescribed for only 2 to 4 weeks.
  • The summary of product characteristics for zopiclone says treatment should stop immediately if a complex sleep behaviour such as sleepwalking occurs.
  • Zopiclone is a Class C drug in Schedule 4 Part 1 of the Misuse of Drugs Regulations.
  • The NHS says zopiclone may not be suitable for people with sleep apnoea or other breathing problems, liver problems, muscle weakness, or a history of alcohol, drug or opioid addiction.
  • The NHS says dependence becomes more likely with longer use, and that a doctor or pharmacist can help someone come off zopiclone gradually, as sleep problems can temporarily return.
  • NICE notes that the risk of dependence and withdrawal should be considered when prescribing Z-drugs, and that rebound insomnia can occur on stopping.
  • In an emergency, such as a suspected overdose or severe withdrawal, call 999; NHS 111 or the GP can advise urgently; Samaritans on 116 123 is free at any time.

Class interactions

Open the Drug Interaction Checker

Connected pages in detail

What each linked page on Anatomy Nexus covers, in a line, for Z-drugs.

Medications

  • Zopiclone Zopiclone is a medicine used to treat insomnia, usually prescribed for just 2 to 4 weeks.
Educational content. A drug class page describes what a family of medicines has in common. Individual medicines differ in dose, licensing and interactions; treatment choices belong to a prescriber.