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 Revex, the reference product, was withdrawn from the market in 2008 for commercial reasons.

The FDA has approved a higher-dose injectable formulation of the opioid antagonist naloxone (Zimhi – Adamis) for emergency treatment of opioid overdose. A single IM or SC injection of the new formulation delivers 5 mg of naloxone; injectable formulations that deliver 0.4 mg or 2 mg of the drug have been available for years. Naloxone is also available in intranasal formulations for the same indication (see Table 1).

The FDA has approved a higher-dose intranasal naloxone formulation (Kloxxado – Hikma) for emergency treatment of opioid overdose. A single spray of the new formulation delivers 8 mg of naloxone; a formulation that delivers 4 mg per spray (Narcan) was approved in 2015.

Use of nonopioid drugs for pain was reviewed in a previous issue. For many types of moderate to severe acute pain, acetaminophen and/or an NSAID may be as effective as an opioid. Immediate-release formulations of full opioid agonists should generally be used for acute pain that is severe enough to require treatment with an opioid. Use of extended-release or long-acting opioid formulations initially and treatment durations >1 week have been associated with an increased risk of unintended long-term use.

The FDA has approved a subcutaneous (SC) extended-release formulation of the mu-opioid receptor partial agonist and kappa-opioid receptor antagonist buprenorphine (Sublocade – Indivior) for once-monthly treatment of moderate to severe opioid use disorder. Sublocade is the first injectable buprenorphine product to be approved in the US. Buprenorphine is also available in sublingual formulations with or without the opioid antagonist naloxone, in a buccal formulation with naloxone, and as a subdermal implant (Probuphine).

Opioid use disorder is a chronic, relapsing disease with both 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 CDC, there were 33,091 deaths related to opioid overdose in the US in 2015, more than in any previous year. Several guidelines on the management of opioid use disorder have recently been published.

Development of abuse-deterrent opioid products, including reformulation of existing products, has become a priority for drug manufacturers and public health advocates. Since our last article on this subject, several new abuse-deterrent opioid formulations have been approved by the FDA, including an oxycodone tablet formulation (Roxybond – Inspirion) that is the first immediate-release opioid product FDA-approved to include claims of abuse deterrence in its labeling. No opioid formulation prevents consumption of a large number of intact dosage units, the most common method of abuse. Abuse-deterrent formulations have one or more properties that make their intentional nontherapeutic use more difficult, less attractive, or less rewarding.

The FDA has approved Arymo ER (Egalet), a new extended-release, abuse-deterrent tablet formulation of morphine sulfate, for management of pain severe enough to require daily, around-the-clock, long-term opioid treatment and for which alternative treatment options are inadequate. Arymo ER can only be marketed to deter abuse by injection because another single-entity, extended-release morphine product, MorphaBond, which has not been marketed to date, has marketing exclusivity for deterrence of abuse by the intranasal route through October 2018.

The FDA has approved Xtampza ER (Collegium), a new extended-release, abuse-deterrent capsule formulation of oxycodone, for management of pain severe enough to require daily, around-the-clock, long-term opioid treatment and for which alternative treatment options are inadequate.

A reader expressed concern that a statement in our article Naloxone (Narcan) Nasal Spray for Opioid Overdose (Med Lett Drugs Ther 2016; 58:1) might be misleading. We stated that heroin has a half-life of 2-6 minutes, which is correct, but heroin is a prodrug that is rapidly metabolized to 6-acetylmorphine and morphine. The risk of respiratory depression is related to those active metabolites, and it may persist well beyond the clearance of heroin from the blood.

The recent increase in deaths due to overdose of heroin and prescription opioids in the US has renewed interest in the opioid antagonist naloxone, particularly in making it available to first responders and to relatives and close friends of persons using heroin or taking prescription opioids. IV or IM administration by healthcare professionals is preferred, but peripheral venous access may be difficult to obtain in IV drug abusers, and exposure to their blood may be hazardous.

Development of abuse-deterrent opioid products, including reformulation of existing products, has become a priority for drug manufacturers and public health advocates. Three available opioid formulations, OxyContin (Purdue), Embeda (Pfizer), and Hysingla ER (Purdue), now include claims of abuse deterrence in their package inserts.

A recent Medical Letter article reported renewed interest in the intranasal administration (off-label) of the opioid antagonist naloxone because of an increase in deaths from opioid overdose in the US.1 Now the FDA has approved a more practical alternative for emergency treatment of life-threatening opioid overdose in adults and children: a single-dose naloxone auto-injector (Evzio – Kaleo) for intramuscular or subcutaneous use.

Evzio will be available in kits containing two prefilled 0.4-mg auto-injectors with voice guidance and a "trainer" device that also has voice guidance, but does not contain medication or a needle. The manufacturer has not published a price for Evzio to date, but news reports indicate that each kit could cost hundreds of dollars, compared to about $20 for a standard 0.4-mg injectable dose of naloxone, which can be given intranasally.

1. Intranasal naloxone for treatment of opioid overdose. Med Lett Drugs Ther 2014; 56:21.

Download complete U.S. English article

The recent increase in deaths from heroin overdose in the US has led to renewed interest in the opioid antagonist naloxone, particularly in making it available as an intranasal spray to paramedics and possibly to relatives and close friends of heroin users. Intravenous (IV) administration is preferred, but peripheral venous access may be difficult to obtain in IV drug abusers, and exposure to their blood may be hazardous.

The Medical Letter review of Palladone (hydromorphone HCl) extended-release capsules (March 14, 2005) warned that a lethal dose could be released if the new formulation was taken with alcohol. Because of that risk, the FDA asked the manufacturer (Purdue) to withdraw the drug from the market (FDA News. July 13, 2005; FDC Reports – “The Pink Sheet” July 18, 2005; 67:3).

A once-daily extended-release (ER) oral formulation of the opioid analgesic hydromorphone hydrochloride (Palladone - Purdue Pharma) has been approved by the FDA for treatment of opioid-tolerant patients with persistent moderate to severe pain. Hydromorphone HCl, a semisynthetic congener of morphine and active metabolite of hydrocodone that has been used since the 1920s, is also available in immediate-release oral, injectable and suppository forms (Dilaudid, and others).

Alprazolam, a short-acting benzodiazepine, is one of the most widely prescribed drugs in the US. It is approved by the FDA for treatment of anxiety and panic disorder. An extended-release formulation, Xanax XR, which can be taken once a day, recently became available for panic disorder.

Methamphetamine, a highly addictive synthetic sympathomimetic, has again become important as a drug of abuse in the US. Its resurgence has been associated with unsafe sexual practices that have resulted in an increase in HIV transmission, particularly among men who have sex with men (SJ Semple et al, J Subst Abuse Treat 2002; 22:149; A Urbina and K Jones, Clin Infect Dis 2004; 38:890).

The FDA has approved the marketing of buprenorphine in sublingual tablets (Reckitt Benckiser) both alone (Subutex) and with naloxone (Suboxone) for treatment of opioid dependence. Previously available only for parenteral use in treatment of pain (Buprenex, and others), it offers an alternative to methadone (Dolophine, and others), which is now often abused (New York Times, February 9, 2003; page 1). As a schedule III narcotic, buprenorphine will be subject to fewer prescribing restrictions than a schedule II drug such as methadone (MJ Kreek and FJ Vocci, J Subst Abuse Treat 2002; 23:93).w1150a

Acute toxic reactions to drugs of abuse continue to be important problems. Some patients may have mixed intoxications with complex combinations of signs and symptoms.

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.

As cocaine continues to be widely available in the USA (Medical Letter, 28:69, 1986), new problems associated with its use continue to emerge. Some recent reports indicate that use of the drug during pregnancy can damage the fetus, lead to abortion or premature labor, and cause toxic effects in the newborn infant.