Tasimelteon is used to treat non-24-hour sleep-wake disorder (non-24; a condition that occurs mainly in people who are blind in which the body's natural clock is out of sync with the normal day-night cycle and causes a disrupted sleep schedule). Tasimelteon is in a class of medications called melatonin receptor agonists. It works similarly to melatonin, a natural substance in the brain that is needed for sleep.
Tasimelteon comes as a capsule to take by mouth. It is usually taken without food once a day before bedtime. Take tasimelteon at the same time every night. If you are unable to take tasimelteon at your usual time, skip that night's dose. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take tasimelteon exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
Swallow the capsules whole; do not open, crush, or chew them.
You may become sleepy soon after you take tasimelteon. After you take tasimelteon, you should complete any necessary bedtime preparations and go to bed. Do not plan any other activities for this time.
Tasimelteon controls non-24-hour sleep-wake disorder but does not cure it. It may take several weeks or months before you feel the full benefit of tasimelteon. Continue to take tasimelteon even if you feel well. Do not stop taking tasimelteon without talking to your doctor.
Tasimelteon is not available in pharmacies. You can only get tasimelteon through the mail from a specialty pharmacy. Ask your doctor if you have any questions about receiving your medication.
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
Before taking tasimelteon,
Unless your doctor tells you otherwise, continue your normal diet.
Skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
Tasimelteon may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
Tasimelteon 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 ( Web Site ) 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).
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. Web Site
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 ( Web Site) 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 Web Site. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.
Keep all appointments with your doctor.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
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.
AHFS® Consumer Medication Information. © Copyright, The American Society of Health-System Pharmacists, Inc., 7272 Wisconsin Avenue, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Selected Revisions: September 15, 2019.