The FDA has approved an intranasal formulation of the opioid antagonist nalmefene (Opvee – Indivior) for emergency treatment of known or suspected opioid overdose in persons ≥12 years old. Nalmefene, which is available by prescription, is the second opioid antagonist to become available as a nasal spray for this indication; the first was naloxone, which is now available for sale over the counter (Narcan, and generic). Other nasal spray formulations of naloxone and injectable formulations of nalmefene and naloxone are available by prescription (see Table 2).

Opioid use disorder is a chronic, relapsing disease with physical and psychiatric components. It is associated with economic hardship, social isolation, incarceration, increased rates of blood-borne infections such as HIV and viral hepatitis, adverse pregnancy outcomes, and increased mortality. According to the NIH, there were 80,411 deaths involving an opioid in the US in 2021, more than in any previous year. Several guidelines on the management of opioid use disorder are available; all recommend maintenance pharmacotherapy as the standard of care.

A new CDC guideline for prescribing opioids for pain recently became available. Nonopioid drugs for pain were reviewed in a previous issue.

The FDA has approved a generic injectable formulation of the opioid antagonist nalmefene (Purdue) for the management of known or suspected opioid overdose. Revex, the reference product, was withdrawn from the market in 2008 for commercial reasons.

Consumption of alcohol has increased during the COVID-19 pandemic. The Diagnostic and Statistical Manual for Mental Disorders, 5th edition (DSM-5) defines alcohol use disorder (AUD; previously called alcohol dependence) as meeting ≥2 of the 11 criteria listed in Table 1 in the past year. The lifetime prevalence of AUD in the US population has been estimated to be about 30%. Despite this high prevalence and the associated morbidity, mortality, and costs, only 3 drugs are FDA-approved for treatment of the disorder.

Acamprosate calcium (Campral - Forest) is now being marketed for oral use to maintain abstinence from alcohol. It has been used in France and other countries since 1989.

Acute toxic reactions to drugs of abuse continue to be important problems. Since the last Medical Letter article on this subject (volume 32, page 92, 1990), new reactions and new approaches to treating them have been reported.

Nalmefene (Revex - Ohmeda), an i methylene analog of naltrexone (Trexan), is a long-acting opioid antagonist that has been approved by the US Food and Drug Administration for reversal of postoperative opioid drug effects, including respiratory depression, sedation and hypotension and for management of known or suspected opioid overdose in the emergency department. The only other opioid antagonists available in the USA are naloxone (Narcan), which is also injectable but has a short duration of action, and naltrexone, which has a long duration of action but is marketed only for oral use.