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Modafinil (By mouth)


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Brand Name(s)


There may be other brand names for this medicine.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Make sure your doctor knows if you are also using dextroamphetamine (Adderall®, Dexedrine®), itraconazole (Sporanox®), ketoconazole (Nizoral®), methylphenidate (Ritalin®), or rifampin (Rifadin®, Rimactane®). Tell your doctor if you are using blood thinners (such as warfarin, Coumadin®) or an MAO inhibitor (such as Eldepryl®, Marplan®, Nardil®, or Parnate®).
  • Your doctor should know if you are also using medicine for depression (such as clomipramine, desipramine, Anafranil®, or Norpramin®) or medicine for seizures (such as carbamazepine, phenobarbital, or Tegretol®).
  • Talk to your doctor if you are also using birth control pills (such as ethinyl estradiol), cyclosporine (Gengraf®, Neoral®, Sandimmune®), diazepam (Valium®), phenytoin (Dilantin®), propranolol (Inderal®), or triazolam (Halcion®).
  • Do not drink alcohol while you are using this medicine.

How to Store and Dispose of This Medicine

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

How to Use This Medicine


  • Your doctor will tell you how much medicine to use. Do not use more than directed.
  • If you use this medicine for daytime wakefulness, take it in the morning. If you use it to stay awake during shift work, take the medicine 1 hour before you begin working.
  • You may take this medicine with or without food.
  • If you have sleep apnea and use a CPAP machine at night, continue using this machine with the medicine.
  • This medicine may not work as well if you use it during a time when you are unusually sleepy.
  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
  • This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.

If a dose is missed:

  • Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
  • If you have missed your dose by more than half a day, skip the missed dose so you will not be kept awake during your normal sleeping hours.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088


Modafinil (moe-DAF-i-nil)

Treats narcolepsy, sleep apnea, and shift work sleep disorder.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Blistering, peeling, or red skin rash.
  • Chest pain.
  • Fast, slow, pounding, or uneven heartbeat.
  • Feeling unusually agitated, aggressive, confused, or excited.
  • Fever, chills, cough, sore throat, and body aches.
  • Mood or mental changes.
  • Numbness, tingling, or burning pain in your hands, arms, legs, or feet.
  • Seeing, hearing, or feeling things that are not there.
  • Severe muscle weakness.
  • Severe nausea, vomiting, or diarrhea.
  • Thoughts of hurting yourself and others.
  • Tremors or shaking.
  • Trouble with breathing.
  • Unusual bleeding, bruising, or weakness.
  • Unusual thoughts or behavior.

If you notice these less serious side effects, talk with your doctor:

  • Anxiety, nervousness, or trouble sleeping.
  • Back pain.
  • Dry mouth.
  • Headache or dizziness.
  • Mild nausea, diarrhea, upset stomach, or loss of appetite.
  • Mild skin rash or itching.
  • Painful menstrual periods.
  • Runny or stuffy nose.

Warnings While Using This Medicine

  • It is important to tell your doctor if you become pregnant. Your doctor may want you to join a pregnancy registry for patients taking this medicine.
  • Make sure your doctor knows if you have kidney disease, liver disease, heart disease, heart rhythm problems, high blood pressure, or have recently had chest pain or a heart attack. Tell your doctor if you have a history of mental illness or drug abuse.
  • Serious skin reactions can occur with this medicine. Stop using this medicine and check with your doctor right away if you have blistering, peeling, or loosening of the skin; red skin lesions; severe acne or skin rash; sores or ulcers on the skin; or fever or chills while you are using this medicine.
  • This medicine may cause a serious type of allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Stop taking this medicine and call your doctor right away if you have a skin rash, itching, hives, hoarseness, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth while you are using this medicine.
  • This medicine may cause serious allergic reactions affecting multiple body organs (e.g., heart, liver, or blood cells). Stop using this medicine and check with your doctor right away if you have the following symptoms: chest pain or discomfort, fever and chills, dark urine, headache, rash, stomach pain, unusual tiredness, unusual bleeding or bruising, or yellow eyes or skin.
  • Birth control pills, implants, shots, patches, vaginal rings, or an IUD may not work well while you are using this medicine. To keep from getting pregnant, use another form of birth control while you are using this medicine and for one month after your last dose. Other forms of birth control include condoms, diaphragms, or contraceptive foams or jellies.
  • This medicine may make you dizzy, drowsy, or you may have trouble thinking or seeing clearly. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.
  • This medicine is not for use with occasional sleepiness that has not been diagnosed as caused by narcolepsy, sleep apnea, or shift-work sleep disturbance.
  • This medicine can be habit-forming. Do not use more than your prescribed dose. Call your doctor if you think your medicine is not working.
  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments. Your blood pressure may need to be checked more often while taking this medicine.

When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to modafinil or other similar medicines (such as armodafinil, Nuvigil®).

Review Date: 7/4/2018
Reviewed By:

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