Learn about many of the available medications in our database.
How does this medication work? What will it do for me?
Suvorexant belongs to the class of medications called hypnotics. It is used to treat difficulties falling or staying asleep. There is a chemical called orexin, which binds to certain receptors in the brain to keep you awake. Suvorexant works by temporarily blocking these receptors.
This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.
Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.
Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.
What form(s) does this medication come in?
Each green, round, film-coated tablet with "33" on one side and plain on the other side, contains 10 mg of suvorexant. Nonmedicinal ingredfients croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, polyvinylpyrrolidone/vinyl acetate copolymer (copovidone – hypromellose, lactose monohydrate, titanium dioxide, triacetin), FD&C Blue No. 1/Brilliant Blue FCF Aluminum Lake and iron oxide yellow.
Each white, oval, film-coated tablet with the Merck logo on one side and "325" on the other, contains 15 mg of suvorexant. Nonmedicinal ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, and polyvinylpyrrolidone/vinyl acetate copolymer (copovidone – hypromellose, lactose monohydrate, titanium dioxide, triacetin).
Each white, round, film-coated tablet, with the Merck logo and "335" on one side and plain on the other, contains 20 mg of suvorexant. Nonmedicinal ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, microcrystalline cellulose, and polyvinylpyrrolidone/vinyl acetate copolymer (copovidone -hypromellose, lactose monohydrate, titanium dioxide, triacetin).
How should I use this medication?
The recommended starting dose of this medication is 10 mg taken once per night, 30 minutes before going to bed. Depending on how well it works and how well you tolerate the medication, your doctor may increase the dose. The maximum recommended dose is 20 mg at bedtime, however the lowest dose that helps you sleep should be used.
Do not take suvorexant if you have less than 7 hours between the time you take the medication and the time you will wake up. It should be taken once per night only.
This medication may be taken with or without food, however it may work slower if you take it with or right after a meal. Grapefruit juice can cause suvorexant to build up in the body, causing increased effects and side effects. Avoid drinking grapefruit juice when taking suvorexant.
Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.
It is important to take this medication exactly as prescribed by your doctor.
If you miss a dose, skip the missed dose and continue with your regular dosing schedule, unless you are able to stay in bed for at least 7 hours. If there is less than 7 hours before you will be waking up, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.
Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.
Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.
Who should NOT take this medication?
Do not take this medication if you:
- are allergic to suvorexant or any ingredients of the medication
- have narcolepsy
What side effects are possible with this medication?
Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.
The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.
The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.
Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.
- dry mouth
- feeling "abnormal"
- feeling sleepy the next day
- unusual dreams
Although most of the side effects listed below don’t happen very often, they could lead to serious problems if you do not seek medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
- extreme sleepiness during the day
- increased sinus/throat infections
- memory problems
- signs of depression or worsening depression (e.g., poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide)
- sleep-paralysis (inability to move or speak when going to sleep or waking up)
- sleep-walking or other activities while sleeping (driving a car, talking, eating)
- temporary weakness in the legs
Stop taking the medication and seek immediate medical attention if any of the following occur:
- thoughts or attempts of suicide
Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.
Are there any other precautions or warnings for this medication?
Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.
Alcohol and other medications that cause drowsiness: Do not combine this medication with alcohol or other medications (e.g., antidepressants, sleeping pills, anxiety medications) that cause drowsiness since additional drowsiness can occur, which can be dangerous.
Breathing: Like other medications that affect the nervous system, suvorexant can suppress breathing. If you have asthma, or another lung disease that increases your risk for breathing difficulties, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
Daytime drowsiness/reduced alertness:Even when taken at the lowest effective dose, suvorexant may cause drowsiness or mental impairment in the daytime. This impairment may not cause symptoms but can cause unsafe activity, such as poor judgement, focus, or reaction time. If you notice that you are drowsy or more frequently want to sleep, stop taking the medication and contact your doctor.
Depression: Suvorexant, like other medications to help with sleep, may cause mood swings and symptoms of depression, including thoughts of self-harm or suicide. If you have depression or a history of depression, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.
If you experience symptoms of depression such as poor concentration, changes in weight, changes in sleep, decreased interest in activities, or notice them in a family member who is taking this medication contact your doctor as soon as possible.
Lactose: This medication contains lactose. If you have hereditary problems of galactose intolerance, lactase deficiency, or glucose-galactose malabsorption, discuss the appropriateness of this medication with your doctor.
Memory disturbance: Medications such as suvorexant can cause memory loss (amnesia). Amnesia of varying severity has been reported following normal doses of this medication. Seniors are more likely to experience this side effect.
Performing activities while not fully awake: People taking suvorexant may perform activities such as sleepwalking, driving, preparing and eating food, and making phone calls while not fully awake and are unaware of their actions. The next morning, they may not remember what happened. This may be more likely to occur if you use alcohol or other sedative medications. If you discover this has happened to you, contact your doctor immediately.
Family members or caregivers of people who are taking this medication should contact the person’s doctor immediately if they notice any of these unusual behaviours.
Other sleep conditions: This medication may cause episodes of sleep paralysis, an inability to move or speak when you are awakening. These episodes may last seconds to several minutes before normal movement is possible.
Suvorexant has also been associated with muscle weakness and waking dreams, mental images that occur during the transition from sleep to wakefulness and also when falling asleep.
Pregnancy: This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.
Breast-feeding: It is not known if suvorexant passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.
Children: The safety and effectiveness of using this medication have not been established for children.
What other drugs could interact with this medication?
There may be an interaction between suvorexant and any of the following:
- antihistamines (e.g., cetirizine, doxylamine, diphenhydramine, hydroxyzine, loratadine)
- antipsychotics (e.g., chlorpromazine, clozapine, haloperidol, olanzapine, quetiapine, risperidone)
- "azole" antifungals (e.g., itraconazole, ketoconazole, voriconazole)
- barbiturates (e.g., butalbital, pentobarbital, phenobarbital)
- benzodiazepines (e.g., alprazolam, diazepam, lorazepam)
- calcium channel blockers (e.g., amlodipine, diltiazem, nifedipine, verapamil)
- chloral hydrate
- general anesthetics (medications used to put people to sleep before surgery)
- grapefruit juice
- HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., delavirdine, efavirenz, etravirine, nevirapine)
- HIV protease inhibitors (e.g., atazanavir, indinavir, ritonavir, saquinavir)
- kava kava
- macrolide antibiotics (e.g., clarithromycin, erythromycin)
- magnesium sulfate
- muscle relaxants (e.g., baclofen, cyclobenzaprine, methocarbamol, orphenadrine)
- narcotic pain relievers (e.g., codeine, fentanyl, morphine, oxycodone)
- protein kinase inhibitors (e.g., crizotinib, imatinib, lapatinib, nilotinib, pazopanib, sunitinib)
- St. John’s wort
- seizure medications (e.g., carbamazepine, clobazam, levetiracetam, phenobarbital, phenytoin, primidone, topiramate, valproic acid, zonisamide)
- selective serotonin reuptake inhibitors (SSRIs; e.g., citalopram, , fluoxetine, paroxetine, sertraline)
- sodium oxybate
- tricyclic antidepressants (e.g., clomipramine, desipramine, imipramine)
If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:
- stop taking one of the medications,
- change one of the medications to another,
- change how you are taking one or both of the medications, or
- leave everything as is.
An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.
Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.
All material copyright MediResource Inc. 1996 – 2022. Terms and conditions of use. The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www.medbroadcast.com/drug/getdrug/Belsomra