Suvorexant is used treat insomnia (difficulty falling asleep or staying asleep). Suvorexant is in a class of medications called orexin receptor antagonists. It works by blocking the action of a certain natural substance in the brain that causes wakefulness.

Suvorexant comes as a tablet to take by mouth. It is usually taken once a day, if needed, no earlier than 30 minutes before bedtime. Suvorexant may be taken with or without food but will begin to work faster if taken on an empty stomach. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take suvorexant exactly as directed. Never take more than one dose of suvorexant per day even if you are still having trouble falling asleep or staying asleep.

You will probably become very sleepy soon after you take suvorexant and will remain sleepy for some time after you take the medication. Plan to go to bed right after you take the medication and to stay in bed for at least 7 hours. Do not take suvorexant if you will be unable to remain asleep for the required number of hours after taking the medication. If you get up too soon after taking suvorexant, you may experience drowsiness and difficulty driving or performing tasks that require alertness.

Your sleep problems should improve within 7 to 10 days after you start taking suvorexant. Call your doctor if your sleep problems do not improve during this time or if they get worse at any time during your treatment.

Your doctor will probably start you on a low dose of suvorexant and may gradually increase your dose if your insomnia does not improve. Your doctor may also decrease your dose of suvorexant or tell you to stop taking the medication if it makes you feel too drowsy during the day.

Swallow the tablets whole; do not split, chew, or crush them.

Suvorexant may be habit forming. Do not take a larger dose, take it more often, or take it for a longer period of time than prescribed by your doctor.

Your doctor or pharmacist will give you the manufacturer’s patient information sheet (Medication Guide) when you begin treatment with suvorexant and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) or the manufacturer’s website to obtain the Medication Guide.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before taking suvorexant,

• Tell your doctor and pharmacist if you are allergic to suvorexant, any other medications, or any of the ingredients in suvorexant tablets. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
• Tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: antifungal medications such as fluconazole (Diflucan), itraconazole (Onmel, Sporanox), ketoconazole, and posaconazole (Noxafil); aprepitant (Emend); boceprevir (Victrelis); carbamazepine (Carbatrol, Equetro); ciprofloxacin (Cipro); clarithromycin (Biaxin, in Prevpac); conivaptan (Vaprisol); digoxin (Lanoxin); diltiazem (Cardizem, Tiazac); erythromycin (E.E.S., Ery-tab); imatinib (Gleevec); certain medications for human immunodeficiency virus (HIV) such as atazanavir (Reyataz), fosamprenavir (Lexiva), indinavir (Crixivan), nelfinavir (Viracept), ritonavir (Norvir, in Kaletra), and saquinavir (Invirase); medications for anxiety, mental illness, pain, and seizures; nefazodone; phenytoin (Dilantin, Phenytek); rifampin (Rifadin, Rimactane); telaprevir (Incivek); telithromycin (Ketek); tricyclic antidepressants such as amitriptyline, amoxapine, clomipramine (Anafranil), desipramine (Norpramin), doxepin (Silenor), imipramine (Tofranil), nortriptyline (Pamelor), protriptyline (Vivactil), and trimipramine (Surmontil); verapamil (Verelan, Covera); sedatives; sleeping pills; and tranquilizers. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• Tell your doctor if you have narcolepsy (a condition that causes extreme daytime sleepiness). Your doctor will probably tell you not to take suvorexant.
• Tell your doctor if you drink or have ever drunk large amounts of alcohol, use or have ever used street drugs, or have overused prescription medications. Also tell your doctor if you are overweight, and if you have or have ever had depression; mental illness; thoughts of harming or killing yourself or trying to do so; chronic obstructive pulmonary disease (COPD; a group of diseases that affect the lungs and airways); sleep apnea (condition in which breathing briefly stops many times during the night); any other lung or breathing problems; muscle weakness that happens suddenly; or liver disease.
• Tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking suvorexant, call your doctor.
• If you are having surgery, including dental surgery, tell the doctor or dentist that you are taking suvorexant.
• You should know that suvorexant may cause drowsiness, decreased mental alertness, and problems with coordination the day after you take it, and these effects may last several days after stopping the medication. This may increase the risk of falls that can cause serious injury, especially if you are elderly. Suvorexant may also impair your driving skills and increase the risk of falling asleep while driving. Your ability to drive or operate machinery the day after you take suvorexant may be impaired even if you feel fully awake. Do not drive a car, operate machinery, or do any dangerous activity within 8 hours of taking suvorexant and until you feel fully awake. Talk to your doctor about the risks of driving or operating machinery after taking suvorexant.
• Do not drink alcohol while you are taking suvorexant. Alcohol can make the side effects from suvorexant worse.
• You should know that some people who took suvorexant got out of bed and drove their cars, prepared and ate food, had sex, made phone calls, or were involved in other activities while partially asleep. After they woke up, these people were usually unable to remember what they had done. Call your doctor right away if you find out that you have been driving or doing anything else unusual while you were sleeping.
• You should know that your behavior and mental health may change in unexpected ways while you are taking this medication. These changes may be caused by suvorexant or they may be caused by physical or mental illnesses that you already have or that you develop during your treatment. Tell your doctor right away if you experience any of the following symptoms: aggressiveness, strange or unusually outgoing behavior, hallucinations (seeing things or hearing voices that do not exist), feeling as if you are outside of your body, memory problems, anxiety, new or worsening depression, thinking about killing yourself or trying to do so, confusion, and any other changes in your usual thoughts, mood, or behavior. Be sure that your family knows which symptoms may be serious so that they can call the doctor if you are unable to seek treatment on your own.

Talk to your doctor about eating grapefruit and drinking grapefruit juice while taking this medication.

This medication is usually taken as needed. You may take suvorexant even if it is later than the usual time, as long as you will be able to remain in bed for the required number of hours after you take it.

Suvorexant may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• Drowsiness
• Dizziness
• Headache
• Unusual dreams
• Dry mouth
• Cough
• Diarrhea

Some side effects can be serious. If you experience any of these symptoms or those listed in the SPECIAL PRECAUTIONS section, call your doctor immediately or get emergency medical treatment:

• Temporary inability to move or speak for up to several minutes while going to sleep or waking up
• Temporary leg weakness during the day or at night

Suvorexant may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from light, excess heat and moisture (not in the bathroom).

Store suvorexant in a safe place so that no one else can take it accidentally or on purpose. Keep track of how many tablets are left so you will know if any are missing.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA’s Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can’t be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

• Extreme drowsiness

Keep all appointments with your doctor.

Do not let anyone else take your medication. Suvorexant is a controlled substance. Prescriptions may be refilled only a limited number of times; ask your pharmacist if you have any questions.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.