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Terms Of Use


Brand Name(s) : Provigil
Side Effects


Modafinil should be used with caution in:

It should not be used in:

Also see list of precautions and interactions


Keep out of sight and reach of children.


What is it used for?

  • Modafinil is used to help people with sleep problems stay awake.
  • It is a centrally acting sympathomimetic, sometimes known as a CNS stimulant.
  • It is used to treat narcolepsy in adults to help them stay awake and an decrease the likelihood of falling asleep in inappropriate situations.
  • In general this drug is used treat excessive sleepiness.
  • Benefits of being on this drug can include improved level and duration of wakefulness and alertness

Listed below are the typical uses of modafinil.

  • Narcolepsy


How often do I take it?

  • Take this medication by mouth, with water, exactly as your doctor has told you.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines.

Do I need to avoid anything?

  • Modafinil can sometimes cause blurred vision, dizziness or excessive sleepiness, if you are affected do not drive or operate machinery. Consult your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.


If any of these persist or you consider them severe then inform your doctor or pharmacist.

Tell your doctor immediately if you develop any of the following symptoms:

If you develop any sign of a rash you should stop taking modafinil and contact your doctor immediately.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking modafinil, tell your doctor or pharmacist if you are allergic to it; or to other centrally acting sympathomimetic; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have:

  • irregular heart beat,
  • uncontrolled moderate to severe high blood pressure (hypertension),
  • allergies to modafinil or any of the other ingredients.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following:

  • History of excessive anxiety, suicidal tendencies, psychosis (loss of contact with reality), depression or mania (over excitation),
  • history of alcohol, drug or illicit substance abuse,
  • high blood pressure (hypertension),
  • kidney disease,
  • liver disease,
  • heart problems,
  • abnormal heart beat,
  • over 65 years of age.

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • Alcohol intake is not known to affect modafinil.

The elderly: modafinil should be used with caution in patients over 65 years of age.

Pregnancy and breast-feeding - please ensure you read the detailed information below


The safety of modafinil has not been established during pregnancy and should not be used if you are, or may be, pregnant. Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Modafinil is not safe to take if you are breastfeeding.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Before using this medicine, tell your prescriber of all the medicines you are taking including prescription medicines and medicines you have bought over the counter without a prescription. Tell your prescriber if you are taking vitamins or complementary remedies such as herbal products, as these can also interact with medicines.

If you are taking more than one medicine, these may interact with each other. Your prescriber may decide to use medicines which interact with each other if the benefit outweighs the risks. In these cases, the dose of your medicines may need to be adjusted or you may be monitored more closely.

The following medicines may interact with modafinil:

  • Hormone contraceptives, including the pill, implants, intrauterine devices (IUDs) and patches
  • Medicines for acid reflux e.g. omeprazole
  • Antiviral medicines
  • Ciclosporin
  • Carbamazepine
  • phenobarbital
  • Phenytoin
  • Medicines for depression and anxiety (tricyclic antidepressants and selective serotonin reuptake inhibitors)
  • Warfarin
  • Calcium channel blockers and other medicines for high blood pressure or heart problems
  • Statins (cholesterol lowering medication)
  • Diazepam
  • Propranolol

This information does not contain all possible interactions. Therefore, tell your prescriber of all the products you are using before taking this medicine.

If you have a question or want to discuss anything about your medicine, speak to your local pharmacist.


If you think you, or someone you care for, might have accidentally taken more than the recommended dose of modafinil or intentional overdose is suspected, immediately contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.
Take the package insert with you.


If you miss a dose, take the next dose at the usual time and resume your usual dosing schedule. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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