Why is Narcan not available over the counter

Naloxone nasal sprayDrug groupsOpioid antagonists Naloxone is an active ingredient from the group of opioid antagonists, which is used in the form of a nasal spray for emergency therapy in the event of an opioid overdose. As a competitive antagonist, naloxone binds to the receptors and neutralizes the effects of the opioids. The spray is given intranasally into a nostril. It is a single dose. Additional doses can be given if necessary. The most common possible adverse effect is nausea.

synonymous: intranasal naloxone, IN-naloxone


The naloxone nasal spray was approved in the USA in 2015 (Narcan®), in the EU in 2017 and in Switzerland in 2018 (Nyxoid®). Each nasal spray contains only one dose and can only be used once.

Structure and properties

Naloxone (C.19H21NO4, Mr = 327.37 g / mol) is a semi-synthetic derivative of morphine. It is present in the drug as naloxone hydrochloride dihydrate, a white, crystalline and hygroscopic powder that is easily soluble in water.


Naloxone (ATC V03AB15) cancels the effects of opioids. The effects are based on the competitive antagonism at opioid receptors. Naloxone has no agonistic activity. It enters the bloodstream via the mucous membrane and the effects occur quickly. Administration is easier than parenteral - intravenous, subcutaneous or intramuscular - naloxone.


For immediate use as emergency therapy for known or suspected opioid overdose manifesting as respiratory and / or central nervous system depression, in both the non-medical and medical settings. For adults and adolescents from 14 years of age. The nasal spray does not replace treatment by an emergency doctor.

Naloxone can be used in an overdose with intoxicants such as heroin as well as with drugs such as oxycodone.


According to the specialist information. The spray is given into a nostril (intranasal). If further doses are required, these are alternately given into the left and right nostrils. A new spray must always be used for this. Depending on the duration of the opioid's effect, it may need to be administered again.


Naloxone has no agonistic properties on the opioid receptor and can therefore not be abused as an intoxicant.


The complete precautionary measures can be found in the medicinal product information sheet.


Drug interactions are possible with opioids, the effects of which are negated by naloxone.

unwanted effects

The most common possible adverse effect is nausea. Other common side effects are:

Due to the abolition of the opioid effects, patients may develop withdrawal symptoms.

see also

Naloxone, opioids, emergency drugs

  • Pharmaceutical product information (EMA, USA)
  • Dwyer K. et al. Opioid education and nasal naloxone rescue kits in the emergency department. West J Emerg Med, 2015, 16 (3), 381-4 Pubmed
  • Gufford B.T. et al. Comparison of a New Intranasal Naloxone Formulation to Intramuscular Naloxone: Results from Hypothesis-Generating Small Clinical Studies. Clin Transl Sci, 2017, 10 (5), 380-386 Pubmed
  • Lewis C.R., Vo H.T., Fishman M. Intranasal naloxone and related strategies for opioid overdose intervention by nonmedical personnel: a review. Subst Abuse Rehabil, 2017, 8, 79-95 Pubmed
  • Madah-Amiri D., Clausen T., Lobmaier P. Rapid widespread distribution of intranasal naloxone for overdose prevention. Drug Alcohol Depend, 2017, 173, 17-23 Pubmed

Conflicts of Interest: None / Independent. The author has no relationships with the manufacturers and is not involved in the sale of the products mentioned.

Support PharmaWiki with a donation!

© PharmaWiki 2007-2021 - PharmaWiki provides independent and reliable information about medication and health.
This article was last changed on 8/8/2018.
Imprint and data protection declaration
Show products for this page