Tasimelteon (By mouth)
Tasimelteon (tas-i-MEL-tee-on)
Treats non-24-hour sleep-wake disorder (non-24) and night time sleep disturbances in patients with Smith-Magenis Syndrome (SMS).
Brand Name(s):
Hetlioz, Hetlioz LQ
There may be other brand names for this medicine.When This Medicine Should Not Be Used:
This medicine is generally considered safe for most people. Talk to your doctor if you have concerns.How to Use This Medicine:
Capsule, Liquid
- Your doctor will tell you how much medicine to use. Do not use more than directed. You may need to use it for several weeks or months before it begins to work for you.
- Take this medicine at the same time every night before bedtime.
- It is best to take this medicine on an empty stomach.
- CapsuleSwallow whole. Do not crush, break, or chew it.
- Oral liquid:
- This medicine comes with an oral dosing syringe and a press-in bottle adapter.
- Shake the bottle for at least 30 seconds before each use.
- Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
- Missed dose: If you cannot take this medicine at about the same time as usual on a given night, skip your dose. Take your regular dose as usual the next night. Do not take extra medicine to make up for a missed dose.
- Capsule: Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
- Oral liquid: Keep it in the refrigerator. Do not freeze. The 48-mL bottle can be stored for 5 weeks and the 158-mL bottle can be stored for 8 weeks first opening the bottle.
Drugs and Foods to Avoid:
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
- Some foods and medicines can affect how tasimelteon works. Tell your doctor if you also use acebutolol, fluvoxamine, ketoconazole, metoprolol, or rifampin.
Warnings While Using This Medicine:
- Tell your doctor if you are pregnant or breastfeeding, if you have liver disease, or if you smoke.
- This medicine may cause some people to become drowsy, sleepy, or less alert than they are normally. It is best to limit your activity after you take this medicine.
- Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments.
- Keep all medicine out of the reach of children. Never share your medicine with anyone.
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
- Change in how much or how often you urinate, difficult or painful urination
If you notice these less serious side effects, talk with your doctor:
- Cough, runny or stuffy nose, sore throat
- Headache
- Nightmares or unusual dreams
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
Last Updated: 9/6/2024
