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Naltrexone

Dependex, Ethylex, Naltrexon Accord · ATC code N07BB04

Also known as: Naltrexon, Naltrekson · Brand names: Dependex, Ethylex, Naltrexon Accord, Adepend, Naltrexon-Hcl Neuraxpharm, Naltrexone Hcl Walter Ritter, Naltrexonhydrochlorid Accord, Nokrev

Key facts
Active substance
Naltrexone
ATC code
N07BB04
Authorisation
authorised nationally; no central EU authorisation
Information as of
2026-10-27

Key facts

Naltrexone is an opioid receptor antagonist. Per the US label it is used in alcohol dependence and to block the effects of exogenously administered opioids, as part of a comprehensive treatment plan.

What it is used for

  • Treatment of alcohol dependence
  • Blockade of the effects of exogenously administered opioids (after detoxification)
  • Only as part of an appropriate plan of management for the addictions

Dosing

  • Patients must be opioid-free (including tramadol) before starting; minimum 7 to 10 days after short-acting opioids
  • Alcoholism: 50 mg once daily is recommended for most patients
  • Opioid dependence: start with 25 mg; if no withdrawal signs, 50 mg a day thereafter
  • When starting and renewing, inform patients about opioid overdose reversal agents (e.g. naloxone)

Contraindications

  • Patients receiving opioid analgesics
  • Current opioid dependence, including maintenance on methadone or buprenorphine
  • Acute opioid withdrawal; failed naloxone challenge or positive urine opioid screen
  • Sensitivity to naltrexone or any component

Important warnings

  • After treatment stops, patients are more sensitive to opioids; previously tolerated doses may cause life-threatening overdose, and fatal cases have been reported
  • Attempts to overcome the blockade with large opioid doses may cause fatal intoxication
  • Hepatitis and clinically significant liver dysfunction have been observed
  • Can precipitate severe withdrawal in opioid-dependent patients

Side effects

  • Common in alcoholism: nausea, headache, dizziness, nervousness, fatigue, insomnia, vomiting, anxiety, somnolence
  • Depression, suicidal ideation and suicide attempts have been reported
  • Hepatocellular injury at higher doses

Interactions

  • Opioid-containing medicines (cough, antidiarrhoeal preparations, analgesics) may not be effective
  • Lethargy and somnolence reported with thioridazine
  • Safety of combination with disulfiram is unknown

Pregnancy and breastfeeding

  • Use in pregnancy only if the benefit justifies the potential risk to the fetus
  • Unknown whether excreted in human milk; caution in nursing women

Summary of the official product information, written with AI (Claude, Anthropic) on 2026-10-28. Every number was checked automatically against the original text. Not reviewed by a physician – the full official text is authoritative.

Full official text →

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For patients

Patient information (US)

This product has no separate US patient information.

Authorisation and brand names by country

Medicines with exactly this active-substance composition, as listed in the national registers – alphabetical and without ranking. Whether a product is currently available is not shown here.

Austria

  • DependexWalter Ritter Gmbh + Co. Kg · 1 register entry
  • EthylexWalter Ritter Gmbh + Co. Kg · 1 register entry
  • Naltrexon AccordAccord Healthcare B.V. · 1 register entry

Source: EMA – Article 57 product data (EU/EEA), as of 2026-10-28

Germany

  • AdependWalter Ritter Gmbh + Co. Kg · 1 register entry
  • Naltrexon-Hcl NeuraxpharmNeuraxpharm Arzneimittel Gmbh · 1 register entry
  • Naltrexone Hcl Walter RitterWalter Ritter Gmbh + Co. Kg · 1 register entry
  • Naltrexonhydrochlorid AccordAccord Healthcare B.V. · 1 register entry

Source: EMA – Article 57 product data (EU/EEA), as of 2026-10-28

Turkey

  • NokrevLİBA LABORATUARLARI A.Ş. · 1 register entry

Source: TİTCK – Ruhsatlı Beşeri Tıbbi Ürünler Listesi, as of 2026-10-16

Brand names in 22 more European countries
Belgium
Naltrexone Accord
Croatia
Adepend, Naltreksonklorid Walter Ritter
Cyprus
Abernil
Czechia
Adepend, Naltrexone Walter Ritter
Denmark
Naltrexon "walter Ritter", Naltrexon Accord, Naltrexone Poa Pharma
Estonia
Naltrexone Accord
Finland
Naldix, Naltrexon Accord, Naltrexon Walter Ritter, Naltrexone Poa Pharma
France
Naltrexone Accord, Naltrexone Viatris
Hungary
Adepend
Ireland
Ethylex, Naltrexone Hydrochloride Accord Healthcare Ireland, Naltrexone Walter Ritter
Italy
Antaxone, Nalorex, Naltrexone Accord Healthcare
Latvia
Naltrexone Accord
Lithuania
Naltrexone Accord
Netherlands
Naltrexon Hcl Walter Ritter, Naltrexon Hydrochloride Accord, Naltrexonhydrochloride Pch
Norway
Naltrexone Accord, Naltrexone Poa Pharma
Poland
Adepend, Naltex
Portugal
Destoxican, Naltrexona Accord, Naltrexona Destoxican
Romania
Naltrexona Amomed, Naltrexona Walter Ritter
Slovakia
Adepend
Slovenia
Adepend, Naltrekson Walter Ritter
Spain
Tranalex
Sweden
Naltrexon Molteni, Naltrexon Vitaflo, Naltrexone Accord, Naltrexone Poa Pharma

EMA – Article 57 product data (EU/EEA), 2026-10-28

Medelix receives no money from pharmaceutical companies. Brand names are listed alphabetically and without ranking.

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Medelix answers clinical questions from guidelines, studies and product information – every claim with its source.

Sources

  1. U.S. Food and Drug Administration. NALTREXONE HYDROCHLORIDE (SpecGx LLC) – Prescribing Information, 2026-09-04. DailyMed (NLM), 2026-10-27. https://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=06ff2d5a-e62b-4fa4-bbdb-01938535bc65
  2. EMA – Article 57 product data (EU/EEA), 2026-10-28. https://www.ema.europa.eu/en/human-regulatory-overview/post-authorisation/data-medicines-iso-idmp-standards-post-authorisation/public-data-article-57-database
  3. EMA – Article 57 product data (EU/EEA), 2026-10-28. https://www.ema.europa.eu/en/human-regulatory-overview/post-authorisation/data-medicines-iso-idmp-standards-post-authorisation/public-data-article-57-database
  4. TİTCK – Ruhsatlı Beşeri Tıbbi Ürünler Listesi, 2026-10-16. https://www.titck.gov.tr/dinamikmodul/85

Editorial: Medelix editorial team · last updated 2026-10-27 · How these pages are made · Report an error

Source: U.S. Food and Drug Administration (FDA), prescribing information, via DailyMed (NLM); public domain. Not advertising, not a treatment recommendation. For questions about your own treatment, ask your doctor or pharmacist.