Modafinil Dosage Guide

What Is Modafinil & How Is It Used?

Modafinil, also known by its brand name Provigil, is a non-amphetamine central nervous system stimulant that is used in conditions that cause excessive daytime sleepiness. It is FDA-approved for use in narcolepsy, shift work disorder, and obstructive sleep apnea.^{1, 2} Off-label, modafinil may be used to treat ADHD, multiple sclerosis-related fatigue, cancer-related fatigue, and acute unipolar and bipolar depressive episodes.³

FDA-approved means that the medication has been reviewed by the FDA and found to be safe and effective for a specific use based on data from clinical trials. When a medication is used off-label, it is for a purpose that the medication is not specifically approved for. It may be prescribed by your doctor using their professional judgment because they believe it may provide you a benefit.

Modafinil Forms & Strengths

Modafinil can be obtained as a generic or by its brand name, Provigil. They are both available as oral tablets and come in two strengths. The right strength and dosage may differ from person to person depending on individual factors such as the condition that is being treated, your age, and any other concurrent conditions such as liver impairment.

Modafinil is available in the following forms and strengths:^{1, 2}

• 100 milligrams (mg) oral tablet
• 200 mg oral tablet

It is important to take medications as prescribed to avoid any unintended or harmful effects. Modafinil should be taken by mouth with or without food. Modafinil will most likely be taken once in the morning, but people with shift work disorder usually take modafinil about 1 hour before their work shift. Taking modafinil later than intended may prevent you from sleeping.

How to Take Modafinil

Modafinil is available as an oral tablet and can be taken with or without food. When taken for narcolepsy or obstructive sleep apnea, modafinil is taken once daily in the morning. For shift work disorder, modafinil is typically taken one hour before your work shift.

Modafinil should be taken as prescribed by your doctor since they will prescribe you the dose that is right for you. When you first take modafinil, do not drive or do other dangerous activities until you know how modafinil affects you. Individuals with sleep disorders should be careful while doing these specific activities.^{1, 2}

Modafinil Dosage for Adults With Narcolepsy

Modafinil is FDA-approved to treat adults with narcolepsy for excessive sleepiness.

Here is modafinil dosage information for adults with narcolepsy:^{1, 2}

• Typical starting dosage: When starting modafinil, patients are typically started on 200 mg taken once in the morning.
• Dosage increases:  Dosage increase is dependent on your doctor’s clinical decision.
• Maximum dosage:  Dosages may be increased up to 400 mg per day, but there is no consistent evidence that this dose had additional benefits beyond that of the 200 mg per day dose.

Modafinil Dosage for Adults With Obstructive Sleep Apnea (OSA)

Modafinil is FDA-approved to treat excessive sleepiness in adults with obstructive sleep apnea. It should be noted that this medication will not treat the underlying obstruction, and other treatments where a continuous positive airway pressure (CPAP) machine may be needed.

Here is modafinil dosage information for adults with obstructive sleep apnea:^{1, 2}

• Typical starting dosage: For obstructive sleep apnea, the recommended dosage is 200 mg per day, usually taken in the morning.
• Dosage increases:  Dosage increases may vary depending on your doctor.
• Maximum dosage:  As with narcolepsy, modafinil dosage may be increased up to 400 mg per day, given as a single dose, but there is no consistent evidence that it provides more benefit than the 200 mg per day dosage.

Modafinil Dosage for Adults With Shift Work Disorder

Modafinil is FDA-approved to treat symptoms of shift work disorder. This condition can develop in people who work outside normal daytime working hours. These individuals do not have a typical sleep-wake schedule, which may lead to problems with wakefulness.

Here is modafinil dosage information for adults with shift work disorder:^{1, 2}

• Typical starting dosage: When treating shift work disorder, 200 mg per day is taken approximately 1 hour before your work shift.
• Dosage increases:  Dosage increases for shift work disorder are not standard.
• Maximum dosage:  Dosages typically stay at 200 mg when treating this disorder.

Factors Influencing Modafinil Dosage

While there are standard dosing practices for modafinil, dosages may be changed depending on individual patient factors. Certain factors, such as age, other medications, and other health conditions, can influence the dosage. For those who have these factors, they may need to start at a lower dosage.

What If I Miss a Dose of Modafinil?

If you miss a dosage of modafinil, you should skip the missed dose. Wait until your next scheduled dose to take your modafinil, then take your normal dosage. Do not double up on your medication to make up for any missed doses. Taking modafinil too late in the day may make it harder for you to go to sleep.

Some patients may stop taking modafinil because they feel better, but it must be taken consistently in order to manage their symptoms. Others stop modafinil due to experiencing side effects during the first week of starting the medication. Typically, these side effects will go away as your body adjusts to the medication when it is taken as prescribed. If you wish to stop modafinil, talk with your doctor first to prevent any unintended side effects and unmanaged symptoms from your disorder.

You should never suddenly stop taking your medication. Talk with your healthcare provider if you would like to stop taking your medication. They will help you create a plan to taper (slowly reduce) the medication.

Modafinil Dosage FAQs

Patients may have questions about their modafinil dosage and what they may expect from taking the medication. Here are some frequently asked questions about modafinil dosage:

Are There Any Risks to Taking Modafinil Long-term?

As with all medications, there are risks involved with taking modafinil. Modafinil is a controlled substance, which means that there is some risk for physical or mental dependence, sometimes known as an addiction. There is not sufficient evidence to suggest that this will occur if taken long-term⁴, but this risk may be reduced if you take modafinil exactly as prescribed. If you have any medical conditions or are taking other medications, let your doctor know so they can address any safety concerns.

How Long Does It Take Modafinil to Work?

Typically, it takes about an hour for a patient to see the effects of modafinil. This is the reason that modafinil is taken 1 hour before a shift for someone with shift work disorder.

Does Modafinil Interact With Birth Control?

Modafinil may interact with hormonal birth control methods, such as birth control pills, shots, implants, patches, vaginal rings, and intrauterine devices (IUDs).^{1, 2} While on modafinil, hormonal birth control methods may not work, leading to a higher chance of getting pregnant while taking modafinil. This effect may exist for one month after modafinil is stopped. If you are on birth control for the purpose of preventing pregnancy, talk with your doctor about birth control methods that may be right for you.

Can Modafinil Be Taken for Depression or for ADHD?

Modafinil is not approved by the FDA to be used in depression or attention-deficit hyperactivity disorder. Although, it has been prescribed off-label for these conditions. There is some evidence modafinil may be effective for ADHD symptoms in children.³ In depression, a small study suggests that it may be helpful in patients who have failed other antidepressant regimens.⁵ More research is needed for both conditions, but if you would like to consider modafinil for an off-label purpose, talk with your doctor.

Can You Overdose on Modafinil?

Overdosing on Modafinil may occur when too much of the medication is taken, whether on purpose or by accident. Overdosages may not only be uncomfortable, but potentially dangerous. An overdose of modafinil may result in changes with your mental state, digestive tract, and cardiovascular system. The symptoms of an overdose may differ from person to person, with some displaying certain effects while others may not.

Signs of an overdose on modafinil include:^{1, 2}

• Insomnia
• Disorientation/confusion
• Hallucination
• Nausea
• Diarrhea
• Slow or fast heart rate
• Chest pain
• Restlessness or agitation
• High blood pressure

What Should You Do If You Take Too Much Modafinil?

If you suspect that too much modafinil has been taken, contact poison control online or by phone (800-222-1222). They are available 24/7 at no charge and can determine the best course of action based on when modafinil was taken, how much was taken, and what symptoms have developed. If the affected person loses consciousness, has a seizure, has trouble breathing, or can’t be awakened, immediate medical care needs to be administered, and 911 should be called.

Questions to Ask Your Healthcare Provider About Modafinil Dosage

When considering taking modafinil, come to your doctor’s appointment with a list of questions to ask. Ask questions pertaining to your expectations of the medication, how it fits into your current health plans, and your potential treatment options. If you are unable to meet a doctor in person, online psychiatry services may be available.

Questions to ask your care team about modafinil dosage include:

• How long will it take for me to adjust to taking modafinil?
• Am I at risk for more serious side effects if I am already taking other anxiety /depression medications?
• What is the best dosage to ensure fewer side effects?
• Is there anything I should tell my therapist about this new medication?
• Are there alternative treatments to modafinil?
• What should I do if I do not see improvement in my symptoms?
• Is modafinil okay to take if I am on birth control?
• How do I know if I need an increased dosage of modafinil?
• How does Modafinil compare to Adderall?