Circadin (insomnia) Tablets

Circadin is a prescription‑only medicine that contains the active ingredient melatonin (2mg per tablet). Unlike standard melatonin supplements that release the active ingredient all at once, Circadin tablets are prolonged‑release (also known as modified‑release). This means the tablet is specially designed to release melatonin slowly and continuously throughout the night, delivering the medicine over approximately 8 to 10 hours.

Circadin is specifically licensed for the short‑term treatment of primary insomnia in adults aged 55 years and older. Primary insomnia means persistent difficulty getting to sleep, staying asleep, or experiencing poor sleep quality that is not caused by another medical condition, mental health issue, or environmental factor. As natural melatonin production tends to decline with age, Circadin is designed to supplement your body's own declining levels and help restore a more natural sleep pattern.

In the UK, Circadin is also occasionally prescribed "off‑label" (outside its official licence) for the prevention and treatment of jet lag (short‑term use for travel across three or more time zones). However, you should always follow the advice of your doctor or pharmacist on the most appropriate treatment for your situation.

Your brain naturally produces a hormone called melatonin. Levels rise in the evening as it gets dark, signalling to your body that it is time to sleep. Levels then fall in the morning as light triggers your brain to stop production, making you feel alert.

Circadin contains synthetic melatonin that is identical to the hormone your body produces naturally. The prolonged‑release formulation is designed to mimic the body's natural release of melatonin over the course of the night. This helps you:

- Fall asleep more quickly
- Stay asleep for longer
- Improve the overall quality of your sleep
- Feel more alert and well‑rested during the day

It is the prolonged‑release action that makes Circadin particularly useful for older adults who have trouble maintaining sleep throughout the night, not just falling asleep at the beginning.

To get the best results, you must take Circadin exactly as directed.

Dosage: The recommended dose is one 2mg tablet once a day.

When to take it: Take the tablet 1 to 2 hours before you plan to go to bed and after food. Taking it after food helps the medicine to be absorbed properly. It is best to take it at the same time each evening to help reset your internal body clock.

How to take it: Swallow the tablet whole with a glass of water. Do not crush, chew, or break the tablet, as this will damage the prolonged‑release coating and prevent it from working properly. The coating is there to ensure the melatonin is released gradually over several hours.

Duration of use: A course of Circadin can be continued for up to thirteen weeks. You should not use it for longer than this without speaking to your doctor.

What if you forget to take a dose? If you forget to take your tablet, take it as soon as you remember before you go to sleep. If you do not remember until the next morning, just skip the missed dose and take your next tablet as usual in the evening. Do not take a double dose to make up for a forgotten one.

What if you stop taking it? There are no known withdrawal effects if treatment is stopped, even if you stop suddenly.

The price for each pack size is shown on this page. What you pay depends on the quantity your prescriber approves, and there is no separate charge for the consultation.

To order, complete the online consultation. A UK-registered prescriber reviews your answers and decides whether Circadin is suitable for you. If it is, we dispense and dispatch it. If it is not, we will tell you why and, where we can, suggest a more appropriate next step. You are not charged for a treatment we cannot supply.

Once you have completed the online consultation and it has been approved, delivery is very fast. Most online pharmacies offer Circadin next day delivery as a standard service.

If your order is approved before the daily cut‑off time (usually mid‑afternoon), it will be dispatched the same day. Your medication will then arrive the next day via a tracked courier service such as Royal Mail Tracked 24. Delivery is often free on orders over a certain amount. The packaging is always discreet – plain and unmarked – so no one else knows what is inside. Once dispatched, you will receive tracking details to follow your parcel's progress to your door.

Some pharmacies also offer click‑and‑collect, allowing you to pick up your order from a local pharmacy branch in as little as two hours after approval.

Like all medicines, Circadin can cause side effects, although not everyone gets them. In clinical studies none occurred in more than 1 in 100 people.

Uncommon effects (up to 1 in 100 people) include headache, back pain, joint pain, inflammation of the nose and throat, drowsiness, dizziness, nausea, abdominal pain, dry mouth, night sweats, rash and itching. Some people report irritability, nervousness, restlessness, vivid dreams or nightmares.

Stop taking it and seek medical advice straight away if you develop swelling of the face, lips or throat, difficulty breathing, or a widespread rash.

Report any suspected side effect through the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk.

Do not take Circadin if any of the following apply to you:

- You are allergic to melatonin or any of the other ingredients in the tablet.
- You have liver disease – its use is not recommended due to lack of safety data.
- You have an autoimmune disease (where the body is 'attacked' by its own immune system) – its use is not recommended due to a lack of clinical data.
- You have been told you have an intolerance to some sugars – the tablets contain lactose. If you have galactose intolerance, a total lactase deficiency, or glucose‑galactose malabsorption, you should not take this medicine.
- You are under 18 years of age – the safety and efficacy of Circadin in children aged 0 to 18 years have not yet been established.
- You are under 55 years of age – Circadin is specifically licensed for adults aged 55 and over for the treatment of primary insomnia. If you are younger than 55, a doctor may still prescribe it "off‑label", but you should discuss this with your clinician.

Use with caution (and speak to your doctor or pharmacist) if:
- You have kidney problems (renal insufficiency)
- You have epilepsy or a history of seizures
- You have a sleep apnoea syndrome (breathing interruptions during sleep)

If you are unsure whether Circadin is right for you, speak to your doctor or pharmacist before taking it.

Yes, Circadin can interact with some other medicines. You should always tell your doctor or pharmacist about any other medicines you are taking, including those bought without a prescription.

Important interactions include:
- Fluvoxamine (an antidepressant) – this can increase melatonin levels in your blood significantly, which can make side effects much more severe.
- Other antidepressants (such as citalopram), sleeping tablets (such as zolpidem), and epilepsy medicines – these may interact with melatonin.
- Caffeine can reduce melatonin levels.
- Smoking (tobacco) can make melatonin less effective, as components of tobacco smoke increase the breakdown of melatonin in the liver.
- Oestrogens (contained in some contraceptives and hormone replacement therapy) may increase melatonin levels.

What about alcohol? Alcohol can reduce the effect of melatonin on sleep. For the best results, you should avoid or limit alcohol while taking Circadin, as alcohol may disrupt your natural sleep cycle and interact with the medicine.

There is limited safety data on the use of melatonin during pregnancy and breastfeeding. Melatonin passes into breast milk, and a risk to the breast‑fed child cannot be excluded.

Melatonin is not recommended during pregnancy or while breastfeeding. If you are pregnant, planning to become pregnant, or are breastfeeding, speak to your doctor before taking this medicine.

Circadin is available on the NHS, but it is restricted in many areas. Most NHS formularies recommend prescribing generic melatonin 2mg modified‑release tablets as the first‑line choice because they are more cost‑effective. Circadin is often reserved for specific situations, such as for children with feeding tubes who require the brand‑name product for administration purposes, or for hospital use only. For most adults, the NHS will prescribe generic melatonin, not Circadin by name. If you want Circadin specifically, you will usually need to obtain it via a private prescription from a registered online pharmacy.

Store below 25°C (room temperature) in a dry place, away from direct sunlight and heat.

Keep the blister pack in its outer carton to protect it from light and moisture.

Keep the medicine out of the sight and reach of children.

Do not use the tablets after the expiry date printed on the packaging.

If you have any leftover tablets, do not throw them away in household waste or pour them down the sink. Take them to your local pharmacy, where they will be disposed of safely.