OTCs Today
Mary Warner
While prescription medications, primarily albuterol, are recommended for most patients with asthma, some patients turn to nonprescription inhalers because of their convenience and price point. Two OTC bronchodilators are FDA approved for use in inhalers: epinephrine (Primatene Mist) and racepinephrine (Asthmanefrin). These medications are intended only for short-term use for mild intermittent asthma. They can treat mild wheezing and difficulty breathing but cannot prevent asthma attacks as albuterol can.
Primatene Mist
Primatene Mist is supplied as a metered dose inhaler and should only be used for temporary relief from asthma symptoms (i.e., as a “rescue inhaler”). It should not be used to treat other breathing-related health conditions, including COPD. Each inhaler contains 160 metered doses of epinephrine and includes a dose counter. Symptoms should be relieved within 20 minutes.
Primatene Mist was removed from the U.S. market in 2011 because it was manufactured with chlorofluorocarbon as the aerosol propellant. It was later approved by FDA in 2018 after the manufacturing process was changed to use hydrofluoroalkane instead.
The recommended dose for adults and children 12 years and older, is one to two inhalations, not to exceed eight inhalations within a 24-hour period. Patients should wait at least 4 hours between doses. Primatene Mist should not be used for children younger than 12 years.
Asthmanefrin
Asthmanefrin was introduced as a cost-effective bronchodilator in 2012, after the discontinuation of Primatene Mist, and is sold in liquid form to be used with a portable nebulizer. Because it must be inhaled through a nebulizer rather than through a metered dose inhaler, it’s not as portable or convenient as Primatene Mist. It also requires preparation before use and therefore may be more susceptible to medication errors.
Asthmanefrin is approved for use in adults and children 4 years and older. The recommended dose is one to three inhalations every 3 hours, not to exceed 24 inhalations during a 24-hour period. Like Primatene Mist, it should not be used for long-term asthma treatment or severe asthma, and symptoms are usually relieved in 10 to 30 minutes.
Warnings and adverse effects
Both Primatene Mist and Asthmanefrin carry a greater risk of adverse effects than prescription medications such as albuterol and levalbuterol. FDA has issued a warning about harmful adverse effects, including chest pain, nausea and vomiting, high BP, dizziness, sinus pain, and trouble sleeping because they contain a form of epinephrine. They may also interact with other medications, most notably MAOIs, stimulants, and other medications that impact neurotransmitters.
It’s also important to recognize that both Primatene Mist and Asthmanefrin can become less effective over time, but patients may not realize the decrease and keep relying on them in a crisis situation. Severe cases of asthma usually require prescription inhalers, and patients should not replace prescription asthma medication with either Primatene Mist or Asthmanefrin.
Finally, because other conditions can cause asthma-like symptoms, patients should not use either of these medications unless they have been diagnosed with asthma.
What to tell your patients
Advise patients not to self-diagnose asthma and not to use either Primatene Mist or Asthmanefrin if they haven’t been officially diagnosed. Patients should also be advised to carefully read the dosage instructions and not to take more doses than the recommended amount. Also caution against using Primatene Mist for patients under 12 years old; children over 4 years old who require nonprescription medication should be given Asthmanefrin. Also advise patients to check with a health care provider before using Primatene Mist or Asthmanefrin if they are currently taking any prescription medication. ■