Skip to main content

Modafinil tablets

Provigil

Take modafinil at the same times each day to avoid missing any doses.

The most common side-effects include headache, feeling sick (nausea) and feeling dizzy.

You should not become pregnant whilst taking modafinil. Ask your doctor about which contraceptive methods are suitable for you while you are taking modafinil - hormonal contraceptives are not suitable.

At a glance

  • Modafinil is a central nervous system stimulant used for daytime sleepiness due to narcolepsy.

  • It helps to control narcolepsy symptoms by increasing alertness and reducing sleepiness.

  • Take modafinil exactly as prescribed by your doctor, usually as a 200 mg daily dose.

  • Do not use modafinil if you are pregnant or trying for a baby.

  • Hormonal contraceptives are less effective when used with modafinil; discuss other options with your doctor.

  • Common side-effects include headache, dry mouth, and feeling sick.

  • See a doctor immediately if you develop a rash, mood changes, or thoughts of harming yourself.

Video picks for Nervous system drugs

Continue reading below

About modafinil

Type of medicine

A central nervous system stimulant

Used for

Daytime sleepiness associated with narcolepsy in adults

Also called

Provigil®

Available as

Tablets

Narcolepsy is a long-term problem that affects your sleep. You feel excessively tired during the daytime but have disturbed night-time sleep. You can also have sleep attacks where you fall asleep at inappropriate times during the day without any warning.

Although there is no cure for narcolepsy, modafinil can help to control your symptoms. Modafinil works by stimulating the central nervous system to increase your alertness and reduce excessive sleepiness during the day.

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking modafinil it is important that your doctor knows:

  • If you are pregnant, trying for a baby or breastfeeding.

  • If you have any problems with the way your liver works or any problems with the way your kidneys work.

  • If you have a heart condition or high blood pressure (hypertension).

  • If you have ever had a mental health problem such as depression, psychosis or mania.

  • If you have ever had a problem with drug or alcohol misuse.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

  • If you have ever had an allergic reaction to a medicine.

Clinical author's note Michael Stewart 01/03/2020: Based on post-marketing reports from the USA, modafinil (Provigil®) may harm an unborn child. Modafinil should not be used during pregnancy. Women of childbearing potential must use effective contraception during treatment with modafinil and for two months after stopping. Discuss with your doctor which forms of contraception are suitable for you, as hormonal contraceptives are made less effective by modafinil. Alternative treatment options for narcolepsy should be used during pregnancy, such as behaviour modifications, good sleeping habits and scheduled daytime naps.

Continue reading below

  • Before you start the treatment, read the manufacturer's printed information leaflet from inside the pack. It will give you more information about modafinil and will provide you with a full list of the side-effects which you may experience from taking it.

  • Take the tablets exactly as your doctor tells you to. There are two strengths of tablet available - 100 mg and 200 mg. When you first start modafinil it is usual to be prescribed a dose of 200 mg daily. You may be asked to take this as a single dose of 200 mg in the morning, or divided into 100 mg in the morning and 100 mg at midday. Your doctor or pharmacist will tell you which is right for you. Your dose may be increased after a little while, depending upon your symptoms.

  • Take your doses with a drink of water to help you swallow the tablet. Do not break or crush the tablet - it should be swallowed whole. You can take modafinil before or after food.

  • If you forget to take a dose, miss out the forgotten dose completely but make sure that you remember to take your next dose when it is due. Do not take two doses together to make up for a forgotten dose.

  • Keep your regular appointments with your doctor so that your progress can be monitored. You may need to have your blood pressure and heart rate checked regularly.

  • Modafinil can cause blurred vision or dizziness in some people and therefore it may affect your ability to use tools or machines, so take care when using them. Sleepiness associated with your condition can add to this.

  • Taking modafinil is not a replacement for a good sleep routine. It is still important that you aim to get around eight hours of sleep at night if possible. You should try to go to sleep and get up at about the same time each day.

  • In the UK, you are required by law to let the Driver and Vehicle Licensing Authority (DVLA) know if you are diagnosed with narcolepsy. You may be allowed to drive again when your symptoms are well controlled with medication, but you will need to have regular reviews. Your doctor will advise you about this.

  • Modafinil should not be used during pregnancy. Women of childbearing potential must use effective contraception during treatment with modafinil and for two months after stopping.

  • Hormonal contraceptives, including oral contraceptive pills, implants, intrauterine contraceptive devices (IUCDs) and contraceptive patches, are less effective when used with modafinil and are therefore not recommended. Speak to your doctor about which contraceptive methods are suitable for you while you are taking modafinil.

  • If you are planning to become pregnant you should stop taking modafinil and try alternative treatment options such as good sleep habits and scheduled daytime naps.

  • If you are having an operation or dental treatment, tell the person carrying out the treatment that you are taking modafinil.

Continue reading below

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the most common ones associated with modafinil. You will find a full list in the manufacturer's information leaflet supplied with your medicine. The unwanted effects often improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following continue or become troublesome.

Common

modafinil side-effects

What can I do if I experience this?

Headache

This usually passes within a day or so, but in the meantime, ask your pharmacist to recommend a suitable painkiller. If the headache continues, speak with your doctor

Dry mouth

Try chewing sugar-free gum or sucking sugar-free sweets

Feeling sick (nausea), indigestion, stomach ache

Stick to simple meals - avoid rich or spicy foods

Diarrhoea

Drink plenty of water to replace lost fluids

Constipation

Try to eat a well-balanced diet and drink several glasses of water each day

Feeling dizzy or tired, blurred vision

Take special care when using tools or machines

Flushing, loss of appetite, nervousness, difficulty sleeping, anxiety, depression, confusion or confused thinking, chest pain, fast heartbeat, numbness or tingling feelings

Speak with your doctor if any of these continue or become troublesome

Important: if you experience any of the following symptoms, stop taking modafinil and contact your doctor for advice straightaway:

  • A rash or blisters on the skin.

  • Any changes to your mood, behaviour, or thinking.

  • Any suicidal thoughts, or thoughts about harming yourself.

If you experience any other symptoms which you think may be due to the tablets, speak with your doctor or pharmacist for further advice.

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

If you buy any medicines, check with a pharmacist that they are suitable to take with your other medicines.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

symptom checker

Unsure about mixing medicines?

Check for possible interactions between medicines, supplements and foods before taking them together.

Frequently asked questions

What is narcolepsy and how does modafinil help?

Narcolepsy is a long-term condition that causes excessive tiredness during the day and disturbed sleep at night. People with narcolepsy can also have 'sleep attacks' where they fall asleep suddenly without warning. Modafinil helps by stimulating the central nervous system to increase alertness and reduce this excessive daytime sleepiness.

Can I take modafinil if I have other health problems?

You should tell your doctor if you have any existing health problems before starting modafinil. This includes issues with your liver or kidneys, heart conditions, high blood pressure, or any history of mental health problems like depression or psychosis. It's also important to mention if you have had drug or alcohol misuse, or any allergies to medicines.

How should I take my modafinil dose?

You should take your modafinil tablets exactly as prescribed by your doctor. They come in 100 mg and 200 mg strengths. Usually, you start with a 200 mg daily dose, which might be taken as one tablet in the morning or divided into 100 mg in the morning and 100 mg at midday. Always swallow the tablet whole with water; do not break or crush it. It can be taken with or without food.

What if I forget to take a dose of modafinil?

If you forget to take a dose, you should miss out that forgotten dose completely. Do not try to take two doses together to catch up. Simply take your next scheduled dose when it is due.

Are there any activities I should be careful with while taking modafinil?

Modafinil can cause blurred vision or dizziness in some individuals. This, combined with the underlying sleepiness from narcolepsy, means you should be cautious when using tools or operating machinery. If you drive, you must inform the DVLA about your narcolepsy, and your doctor will advise you about driving safely once your symptoms are well controlled.

Can modafinil affect contraception?

Yes, modafinil can make hormonal contraceptives, such as oral contraceptive pills, implants, IUCDs, and patches, less effective. These methods are generally not recommended when taking modafinil. Women of childbearing potential must use effective contraception during treatment and for two months after stopping. You should discuss suitable contraceptive methods with your doctor.

What should I do if I experience side-effects from modafinil?

Many common side-effects, like headache or dry mouth, often improve as your body adjusts. For a headache, a suitable painkiller from your pharmacist might help. For a dry mouth, try sugar-free gum or sweets. However, if any side-effects continue or become troublesome, you should speak with your doctor or pharmacist. It's crucial to stop modafinil and contact your doctor immediately if you develop a rash or blisters, notice any changes in mood, behaviour, or thinking, or experience suicidal thoughts.

Further reading and references

Continue reading below

About the authorView full bio

Author image

Michael Stewart, MRPharmS

Medicine Leaflet Review Manager – Contractor, Pharmacist

BPharm (Hons), MRPharmS

Michael is a community pharmacist practicing in the Midlands and South Yorkshire with more than 20 years’ experience advising on medicines and medical conditions. He has a strong background in healthcare training, having produced and delivered training courses for pharmacy teams and staff of residential care settings, including nurses. He has also contributed to pharmacy advisory boards for the management of low acuity conditions in the community.

About the reviewer

Author image

Sid Dajani

Sultan Dajani qualified at the London School of Pharmacy in 1994 and became the youngest elected member of the Royal Pharmaceutical Society council since its founding in 1842.

Article history

The information on this page is written and peer reviewed by qualified clinicians.

flu eligibility checker

Ask, share, connect.

Browse discussions, ask questions, and share experiences across hundreds of health topics.

Sign up to the Patient newsletter

Your weekly dose of clear, trustworthy health advice - written to help you feel informed, confident and in control.

Please enter a valid email address

By subscribing you accept our Privacy Policy. You can unsubscribe at any time. We never sell your data.