Tasimelteon: Uses, Side Effects, Dosage - Drugvu

ℹ️ Compiled from public regulatory records · Last regulator revision: December 4, 2025🚩 Report this page

Tasimelteon

Melatonin Receptor Agonists

Sold as Hetlioz

GB MHRAEU EMA

Drug class: Melatonin Receptor Agonists
Availability: See label
Markets covered: 2
Products on record: 3

Overview

Tasimelteon is an active pharmaceutical ingredient in the Melatonin Receptor Agonists group (N05CH). The information below is compiled per regulator from the product labels on record, with direct links to the original documents.

Regulatory status by market

Market	Regulator	Products	Last revision
GB United Kingdom	MHRA	2	July 11, 2025
EU European Union	EMA	1	December 4, 2025

GBUnited Kingdom· MHRA

2 products

Uses

GBOfficial regulatory label· revised May 20, 2022[1]

HETLIOZ is indicated for the treatment of Non-24-Hour Sleep-Wake Disorder (Non-24) in totally blind adults.

How to take

EUEuropean Union· EMA

1 product

Uses

EUOfficial regulatory label· revised December 4, 2025[2]

HETLIOZ is indicated for the treatment of Non-24-Hour Sleep-Wake Disorder (Non-24) in totally blind adults.

How to take

Drug interactions

Known interactions involving Tasimelteon. Select one for details. This list is informational and not a complete interaction checker.

Alfentanil Apalutamide Benzhydrocodone Buprenorphine Butorphanol Carbamazepine Ciprofloxacin Codeine Dezocine Dihydrocodeine Enoxacin Enzalutamide Fentanyl Fluvoxamine Fosphenytoin Hydrocodone Hydromorphone Levorphanol Lumacaftor Meperidine Methadone Mitotane Morphine Nalbuphine Oliceridine Oxycodone Oxymorphone Pentazocine Phenobarbital Phenytoin Primidone Propoxyphene Remifentanil Rifabutin Rifampin Rifapentine Sufentanil Tapentadol Tramadol Abametapir Acebutolol Albendazole Aldesleukin Alprazolam Aminoglutethimide Amiodarone Amitriptyline Amobarbital Amoxapine Amprenavir Anagrelide Apomorphine Apraclonidine Aprepitant Aripiprazole Armodafinil Asenapine Atazanavir Atenolol Azatadine Azelastine Baclofen Berotralstat Betaxolol Bexarotene Bicalutamide Biperiden Bisoprolol Boceprevir Bosentan Brexanolone Brexpiprazole Brimonidine Brivaracetam Bromocriptine Brompheniramine Buspirone Butabarbital Butalbital Cannabidiol Capmatinib Carbinoxamine Cariprazine Carisoprodol Carteolol Carvedilol Cenobamate Ceritinib Cetirizine Chlorcyclizine Chlordiazepoxide Chlormezanone Chlorphenesin Chlorpheniramine Chlorpromazine Chlorzoxazone Cimetidine Citalopram Clarithromycin Clemastine Clobazam Clomipramine Clonazepam Clonidine Clorazepate Clotrimazole Clozapine Cobicistat Conivaptan Crizotinib Cyclizine Cyclobenzaprine Cyproheptadine Dabrafenib Dalfopristin Dantrolene Darunavir Deferasirox Delavirdine Desipramine Desvenlafaxine Deutetrabenazine Dexamethasone Dexbrompheniramine Dexmedetomidine Dextromethorphan Diazepam Dichloralphenazone Difenoxin Diltiazem Dimenhydrinate Diphenhydramine Diphenoxylate Doxepin Doxylamine Dronabinol Dronedarone Droperidol Duloxetine Duvelisib Efavirenz Elagolix Entacapone Erythromycin Escitalopram Esketamine Eslicarbazepine Esmolol Estazolam Eszopiclone Ethanol Ethchlorvynol Ethosuximide Ethotoin Etravirine Ezogabine Fedratinib Felbamate Flavoxate Flibanserin Fluconazole Fluoxetine Fluphenazine Flurazepam Fosamprenavir Fosaprepitant Fospropofol Fostamatinib Gabapentin Givosiran Grepafloxacin Griseofulvin Halazepam Haloperidol Hydroxyzine Idelalisib Ifosfamide Iloperidone Imatinib Imipramine Indinavir Isavuconazonium Isocarboxazid Isoniazid Itraconazole Ivacaftor Ivosidenib Ketamine Ketoconazole Labetalol Lamotrigine Larotrectinib Lasmiditan Lefamulin Lemborexant Letermovir Levetiracetam Levobetaxolol Levobunolol Levocetirizine Lithium Carbonate Lofexidine Lonafarnib Lorazepam Lorlatinib Loxapine Lumateperone Lurasidone Maprotiline Meclizine Mephenytoin Mephobarbital Meprobamate Mesoridazine Metaxalone Methdilazine Methocarbamol Methotrimeprazine Methsuximide Metipranolol Metoclopramide Metoprolol Metreleptin Metyrosine Mexiletine Miconazole Midazolam Mifepristone Mirtazapine Modafinil Molindone Nabilone Nadolol Nafcillin Nebivolol Nefazodone Nelfinavir Netupitant Nevirapine Norfloxacin

Showing 240 of 358. Type above to find a specific drug.

Interaction data compiled from DDInter (academic, CC-BY). Severity classification only - this is not a complete interaction checker and not medical advice.

Sources & citations

[1]MHRA (UK) · PLGB434600001 · revised May 20, 2022
[2]European Medicines Agency · EMEA/H/C/003870 · revised December 4, 2025

Information on this page is compiled from public regulatory records. Drugvu is not affiliated with any regulator or pharmaceutical manufacturer. This is not medical advice. Always consult a qualified healthcare professional.

Side effects & warnings

GBOfficial regulatory label· Adverse reactions· revised May 20, 2022[1]

1%). The most frequently reported adverse reactions were mostly mild to moderate in severity and transient in nature. 3% of tasimelteon- treated patients. 17%). Tabulated list of adverse reactions The following are adverse reactions that were reported in tasimelteon-treated adult patients, derived from patient trials in 1772 patients treated with tasimelteon.
The following terms and frequencies are applied and presented by MedDRA System Organ Class: Very common (≥1/10); Common (≥1/100 to <1/10); Uncommon (≥1/1,000 to <1/100); Rare (≥1/10,000 to <1/1,000); Very rare (<1/10,000). Within each frequency grouping, adverse reactions are presented in order of decreasing seriousness.
Table 1:
Summary of Adverse Drug Reactions System Organ Class Very common Common Uncommon Psychiatric disorders Sleep disorder, insomnia, abnormal dreams Nightmare Nervous system disorders Headache Somnolence, dizziness Dysguesia Ear and labyrinth disorders Tinnitus Gastrointestinal disorders Dyspepsia, nausea, dry mouth Renal and urinary disorders Pollakiuria General disorders and administrative site conditions Fatigue Foggy feeling in head Investigations Alanine aminotransferase increased Aspartate aminotransferase increased, gamma- glutamyl transferase increased Reporting of suspected adverse reactions Reporting suspected adverse reactions after authorisation of the medicinal product is important.
It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the national reporting system listed in Appendix V.

GBOfficial regulatory label· Warnings and precautions· revised May 20, 2022[1]

After taking tasimelteon, patients should limit their activity to preparing for going to bed. 5). 5). Patients should be instructed to initiate tasimelteon treatment without regard to circadian phase. Physicians should evaluate patient response to tasimelteon 3 months after treatment initiation utilising a clinician interview to assess their overall functioning with an emphasis on sleep-wake complaints.
Excipients HETLIOZ hard capsules contain lactose. Patients with rare hereditary problems of galactose intolerance, total lactase deficiency or glucose- galactose malabsorption should not take this medicinal product. HETLIOZ hard capsules contain the azo colouring agent Orange Yellow S (E110), which may cause allergic reactions.
This medicinal product contains less than 1 mmol sodium (23 mg) per hard capsule, that is to say essentially ‘sodium-free’.

This is not medical advice. Consult a qualified healthcare professional.