Insomnia is one of the most common sleep disorders thought to affect around 1 in 3 of us at some point in our lives. The symptoms and severity of insomnia vary significantly from person to person, however, the disorder is generally characterised as a difficulty getting to sleep or staying asleep for long enough to feel refreshed the next morning. 

Treatments for insomnia include changing your sleeping habits, Cognitive Behavioural Therapy (CBT), and if necessary, sleeping pills. In this piece, we take a close look at two types of insomnia medications - Zopiclone and Circadin, to compare how they work, the way they’re taken, their effectiveness and more. 

What is Zopiclone?

Zopiclone is a type of sleeping pill that contains the hypnotic agent Zopiclone. This active ingredient targets the GABA receptors in the brain, resulting in a sedative effect. This medication is used to help treat insomnia in adults and elderly people who struggle with the disorder. 

What is Circadin?

Circadin is also a type of medication used to treat insomnia, however, this drug is solely intended for those who are aged 55 or over. Circadin contains the sleep hormone Melatonin, which works alongside your body’s circadian rhythm to let your mind and body know when it’s time to sleep.  

What is the difference between Zopiclone and Circadin?

zopiclone vs circadin


Both of these medications come in tablet form. Zopiclone tablets are available in two different strengths, 3.75 mg and 7.5 mg. They are available in boxes containing 28 pills. Circadin, on the other hand, is available in 2 mg doses and can be found in boxes of either 30, 60 or 90. 

Who can take them?

Zopiclone is designed for adults suffering from insomnia. This medication is not suitable for people who:

  • Are under the age of 18
  • Are currently pregnant or breastfeeding 
  • Suffer from irregular breathing while asleep
  • Are allergic to any of the ingredients
  • Have a condition called Myasthenia Gravis 
  • Are currently taking any other medications that could interact with Zopiclone (please see the Zopiclone patient information leaflet for more information). 

It’s important to speak to your doctor before taking this medication. Particularly if you are elderly, suffer from kidney or liver problems, have a history of breathing difficulties, have suffered from mental illness or have ever had a history of alcohol or drug abuse. 

Circadin is only intended for the treatment of primary insomnia. Primary insomnia refers to a sleep disorder that has no identified cause, including medical, mental or environmental causes. It should only be used by adults aged 55 and above, and is not suitable for the following

  • Those aged 0 to 18
  • People with allergies to any of the medication’s ingredients 
  • Those who are pregnant or breastfeeding 
  • People with kidney or liver problems
  • People with an intolerance to certain sugars 
  • Those with auto-immune diseases
  • If you have recently taken any medications that may interact with this drug (these are outlined on the Circadin patient information leaflet). 

Smoking and drinking alcohol may reduce the effectiveness of Circadin. Always consult a doctor before starting any new medication. 

Dosage instructions

Zopiclone tablets are designed to be swallowed whole with a glass of water. The recommended doses are as follows: 

Adults: Two 7. 5mg tablets a day immediately before going to bed. 

Elderly, frail or patients with reduced kidney, liver or lung function: A starting dose of 3.75 mg a day, to be taken immediately before going to bed.  

Do not exceed these doses. Zopiclone is only intended for short term use (anywhere between a few days to up to two weeks). Use of this medication should not exceed 4 weeks, including a period of tapering off. 

Circadin should also be swallowed whole with some water. The recommended dose for this medication is: 

Adults: One 2 mg Circadin tablet a day to be taken by mouth, after food, 1-2 hours before bedtime. 

This dosage may be continued for up to 13 weeks. Circadin tablets should not be crushed or cut in half. 

Side effects

As with any medication, there is a range of side effects associated with Zopiclone and Circadin. A full list of side effects for each drug can be found in their patient information leaflets, but here are the most common: 

Zopiclone: Sleepiness during the following day, reduced alertness, bitter taste in the mouth and dry mouth.

Circadin: Nausea, anxiety, diarrhoea, headaches, lethargy and nightmares.

If you experience any of the following symptoms whilst taking these medications, stop taking the drug and seek medical assistance immediately: 

Zopiclone: Allergic reaction: skin rash, itching, swelling of the face, lips, throat or tongue, difficulty breathing or swallowing. 

Circadin: Chest pain, loss of consciousness or fainting, severe chest pain due to angina, feeling your heartbeat , depression, visual impairment, blurred vision, disorientation , vertigo (a feeling of dizziness or “spinning”), presence of red blood cells in the urine, reduced number of white blood cells in the blood or reduced blood platelets (which increases risk of bleeding or bruising  psoriasis). 


Zopiclone tablets cost approximately £2.68 each on the Doctor 4 U website, whereas Circadin tablets are priced at around £1.00 each.  

A box of 28 x 3.75 mg Zopiclone tablets comes to £74.99, with a box of 7 x 7.5 mg tablets costing £24.99. A box containing 30 Circadin tablets costs £29.99. 


Zopiclone first underwent clinical testing in 1986. The study found that the drug helped to improve sleep in both healthy volunteers and sufferers of insomnia. The report states, “after Zopiclone, sleep duration and quality increased, and sleep onset time and the number of awakenings decreased further than after placebo”. Since it’s initial testing, Zopiclone has since been established as an effective treatment for sufferers of insomnia and is now widely prescribed to sufferers of the condition who struggle to manage the disorder with other treatments. 

A study of Melatonin (the active ingredient found in the drug Circadin) was conducted on patients aged 55 to 80 to assess the efficacy of the medication as a treatment for insomnia. The results found a significant reduction in sleep latency (the time it takes patients to fall asleep) while taking the pills. The findings also concluded that participants’ quality of life was improved significantly during these trials.  

We hope this article has provided you with a good overview of the similarities and differences between Zopiclone and Circadin to help you decide which insomnia sleeping pill might be the most suitable for you. It’s important to note that before starting any new medication, you should always consult a doctor first, who will be able to advise you based on your individual needs and circumstances.