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Tasimelteon Side Effects

For the Consumer

Applies to tasimelteon: oral capsule

As well as its needed effects, tasimelteon may cause unwanted side effects that require medical attention.

Severity: Moderate

If any of the following side effects occur while taking tasimelteon, check with your doctor or nurse as soon as possible:

More common:
  • Bladder, lower back, or side pain
  • bloody or cloudy urine
  • difficult, burning, frequent, or painful urination

Minor Side Effects

Some tasimelteon side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:

More common:
  • Body aches or pain
  • chills or fever
  • cough
  • ear congestion
  • headache
  • nasal congestion, runny nose, or sneezing
  • nightmares

For Healthcare Professionals

Applies to tasimelteon: oral capsule

Nervous system

Very common (10% or more): Headache (17%)
Frequency not reported: Somnolence[Ref]

Hepatic

Very common (10% or more): Increased ALT (10%)[Ref]

Psychiatric

Very common (10% or more): Nightmare/abnormal dreams (10%)

Genitourinary

Common (1% to 10%): Urinary tract infection[Ref]

Respiratory

Common (1% to 10%): Upper respiratory tract infection[Ref]

References

1. "Product Information. Hetlioz (tasimelteon)." Vanda Pharmaceuticals Inc, Rockville, MD.

It is possible that some side effects of tasimelteon may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.

Disclaimer: Every effort has been made to ensure that the information provided is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. This information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate safety, effectiveness, or appropriateness for any given patient. Drugs.com does not assume any responsibility for any aspect of healthcare administered with the aid of materials provided. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the substances you are taking, check with your doctor, nurse, or pharmacist.

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