Melatonin is a prescription-only medication that you can take to treat short-term insomnia. Your body naturally produces the hormone melatonin, which is essential for regulating and preparing your body for sleep.

Melatonin tablets are prescribed to help you fall asleep more quickly and help you stay asleep during the night. It is available as oral tablets, slow-release tablets, capsules, and liquid. At Superdrug Online Doctor, we only offer melatonin tablets. In addition to generic melatonin, it is available under several brand names, including Circadin, Adaflex, and Syncrodin.

Melatonin tablets work by mimicking the natural melatonin produced by the brain. Melatonin regulates your internal body clock (circadian rhythm) and rises in the evening as it gets dark, signalling to your body that it is time to sleep. Melatonin tablets can enhance this effect, especially when natural production is interrupted, impacting your sleep.

If you have insomnia, your melatonin levels may be low, although this is not always the case. However, melatonin tablets can help your body prepare for sleep and limit the chance of waking during the night.

How long does melatonin last?

The effects of melatonin tablets usually last for 4 to 8 hours, helping you get a restful, uninterrupted night’s sleep.

How long does melatonin stay in your system?

Standard-release melatonin tablets will usually stay in your system for 4 to 8 hours.

How long does melatonin take to work?

Melatonin usually takes effect within 30 to 60 minutes after taking it, but this can vary from person to person. For example, it may work as quickly as 20 minutes for some people and 1 to 2 hours for others.

How effective is melatonin?

One study found that melatonin helps people fall asleep 7 minutes faster and increases total sleep time by 8 minutes on average.

A study examining the effectiveness of slow-release 2mg melatonin tablets found that 47% of people had a significant improvement in sleep quality and morning alertness, compared with 27% of people given a placebo.

Is melatonin safe?

Yes, melatonin is generally considered safe if it has been prescribed to you by a doctor. It’s usually prescribed to treat short-term sleep issues and insomnia and is not intended for long-term use.

At Superdrug Online Doctor, our doctors can prescribe melatonin tablets for insomnia, which should be swallowed whole with a glass of water, after food.

When to take melatonin

You should take melatonin 2mg slow-release tablets 1 to 2 hours before going to bed. This allows enough time for your melatonin levels to rise and promote sleep.

How much melatonin to take

The usual dose of melatonin for insomnia is one 2mg tablet per day, taken in the evening before bed.

How long do you need to take melatonin for?

Melatonin for insomnia is only intended for short-term use. It’s usually recommended for 1 to 4 weeks, but no longer than 13 weeks.

What if I miss a dose of melatonin?

If you forget to take your melatonin tablet, take one as soon as you remember before going to bed, or wait until it is time for your next dose. Then continue taking your tablets as usual. Do not take a double dose to make up for a missed dose.

What if I take too much melatonin?

If you take more melatonin than you should, it can make you feel drowsy. Contact your doctor as soon as possible for more advice if you have taken too much melatonin.

Can you overdose on melatonin?

Yes, it is possible to overdose on melatonin or take too much, which can lead to unpleasant side effects.

Can you take melatonin every night?

Yes, melatonin can be taken every night for up to 13 weeks to treat insomnia. Sometimes a doctor may recommend that you take melatonin only 2 or 3 times a week at first to see if it helps you sleep, before taking it every night.

Melatonin tablets are only available with a prescription in the UK. You may be able to get them on the NHS or with a private prescription from an online doctor service.

Can I buy melatonin online?

Yes, you can buy slow-release 2mg melatonin tablets online from Superdrug Online Doctor. To request melatonin for insomnia, you will need to:

1. Fill out a short online health questionnaire for one of our doctors to review.
2. Complete your payment and choose your delivery options.
3. Once approved, we will deliver your medication to your address in plain, discreet packaging, or you can choose to collect it from your nearest Superdrug Pharmacy.
4. If your request is not approved, one of our doctors will recommend an alternative.

Can I buy melatonin over the counter?

No, melatonin is a prescription-only medication, which means you must have a doctor's approval before getting it.

Can I get melatonin on the NHS?

Yes, melatonin may be available on the NHS for sleep problems, like insomnia, for adults over 55 or those with chronic sleep disorders. You will need to make an appointment with your GP to find out if it is suitable and available.

Like all medications, melatonin can cause side effects, although not everyone will get them.

Uncommon side effects (may affect up to 1 in 100 people) are:

• mood changes like restlessness, nervousness, and irritability
• headaches
• migraine
• insomnia
• dizziness
• feeling weak
• tiredness
• high blood pressure
• mouth ulcers
• abdominal pain
• night sweats
• pain in the extremities
• abnormal liver function
• weight gain
• skin problems
• indigestion
• changes in blood composition
• abnormal dreams, nightmares
• anxiety
• restlessness associated with increased activity
• dry mouth
• nausea (feeling sick)
• inflammation of the skin
• itching, rash, dry skin
• menopausal symptoms
• glucose (sugar) in the urine, excess proteins in the urine

Rare side effects (may affect up to 1 in 1000 people) include:

• shingles
• high level of fatty molecules in the blood
• low serum calcium levels in the blood, low sodium levels in the blood
• altered mood, such as aggression, agitation, crying, stress symptoms
• early morning awakening
• increased sex drive (libido)
• depressed mood
• memory impairment
• disturbance in attention, dreamy state
• restless legs syndrome
• poor quality sleep
• ‘pins and needles’ feeling
• watery eyes
• dizziness when standing or sitting
• hot flushes
• acid reflux, stomach disorder
• blistering in the mouth, tongue ulceration
• stomach upset
• vomiting (being sick)
• abnormal bowel sounds, wind
• excess saliva production, bad breath
• abdominal discomfort, gastric disorder, inflammation of the stomach lining
• eczema, skin rash, hand dermatitis, itchy rash, nail disorder
• arthritis
• muscle spasms
• neck pain
• night cramps
• prolonged erection that might be painful
• inflammation of the prostate gland
• tiredness
• pain
• thirst
• passing large volumes of urine, urinating during the night
• increased liver enzyme
• abnormal blood electrolytes and abnormal laboratory tests

For a full list of potential melatonin side effects, please read the patient information leaflet that comes with your medication.

How long do melatonin side effects last?

Most melatonin side effects should go away within 5 to 8 hours when the active ingredient leaves your body. If they continue to get worse or are difficult to manage, speak to your doctor for more advice.

What to do if you get melatonin side effects

You can manage most mild side effects at home in the following ways:

• headache – drink plenty of water to stay hydrated and take over-the-counter painkillers, like paracetamol and ibuprofen
• feeling or being sick – take melatonin tablets after food and eat simple meals, avoiding spicy or rich foods, it can also help to eat smaller, more frequent meals
• dizziness – sitting or lying down until you feel better can help, also avoid alcohol, which can make dizziness worse
• dry mouth – it can help to suck sugar-free sweets or chew sugar-free gum and drink plenty of water
• dry or itchy skin – regularly apply moisturiser to your skin, and if it does not improve within a week, contact your doctor for advice

If you get any of the following serious side effects, call 999 or get someone to take you to A&E:

• swelling of your lips, tongue, mouth, or throat
• difficulty breathing or swallowing
• your skin, tongue, or lips turn blue, grey, or pale
• you suddenly become very confused, drowsy or dizzy
• fainting
• a swollen, raised, itchy, blistered, or peeling rash

Melatonin is a short-term treatment for insomnia in adults. However, it may not be suitable for everyone, which is why a doctor will need to check if it is safe for you.

Do not take melatonin if you:

• are allergic to melatonin or any other ingredient listed in the medication
• have an autoimmune disorder, such as rheumatoid arthritis, multiple sclerosis, or lupus
• have liver or kidney problems

Before taking melatonin, tell your doctor if you:

• are intolerant to some sugars
• smoke (tobacco smoke can make melatonin less effective)
• drive or use machinery for a living because melatonin can make you feel drowsy

Melatonin and other medications

You must tell a doctor about any prescribed, over-the-counter, or herbal medications you are taking before starting melatonin, including:

• fluvoxamine
• cimetidine
• quinolones
• rifampicin
• oestrogen
• carbamazepine
• adrenergic agonists/antagonists
• opiate agonists/antagonists
• prostaglandin inhibitors
• antidepressants
• tryptophan
• alcohol
• benzodiazepines and non-benzodiazepine hypnotics
• thioridazine

Melatonin and pregnancy and breastfeeding

Do not take melatonin if you are pregnant, thinking about getting pregnant, or breastfeeding.

Melatonin and food and drink

Ideally, you should take melatonin after you have eaten. Do not drink alcohol before, during, or after taking melatonin, as it can reduce its effectiveness.

Melatonin is not the only treatment available for insomnia. At Superdrug Online Doctor, we can also provide Quviviq, a prescription-only medication that contains daridoxerant.

There are also over-the-counter sleep aids that often contain sedative antihistamines or herbal products, such as valerian root, to promote sleepiness. However, research supporting their effectiveness is limited; some, like valerian, may help improve sleep quality and reduce insomnia symptoms.

Melatonin vs Quviviq

Melatonin and Quviviq are available in the UK for insomnia. Melatonin is a short-term treatment that can be prescribed for up to 13 weeks, while Quviviq may be a more long-term treatment as it can be taken for up to 1 year. Melatonin works by topping up your natural melatonin levels to help your body prepare for sleep.

Quviviq contains the active ingredient, daridoxerant, which works by binding to orexin receptors in the brain to block signals that keep you awake. Research shows that Quviviq is 53% effective at improving sleep within a week.

Why is melatonin prescription-only in the UK?

Melatonin is a prescription-only medication in the UK because it is a regulated pharmaceutical drug and needs to be monitored for side effects. A doctor must monitor your body’s response to melatonin and ensure you are not currently taking any medication or have an underlying condition that may interact with melatonin.

Is melatonin legal in the UK?

Yes, melatonin is legal in the UK if it has been prescribed to you by a doctor or healthcare professional. It is prescribed for jet lag or insomnia. It is only available with a prescription and is not available over the counter.

Is melatonin bad for you?

Melatonin is generally considered safe for short-term treatment of insomnia. You must take it only as your doctor tells you to and for a maximum of 13 weeks, or until your doctor tells you to stop.