Non-prescription racemic epinephrine for asthma
Published Online: April 18, 2014
Inhaled racepinephrine (Asthmanefrin®) became available in September 2012 as a non-prescription treatment for asthma symptoms. It comes with a handheld electronic device that turns the liquid into a mist inhaled by the patient. The manufacturer, Nephron Pharmaceuticals, is promoting this as an alternative to an epinephrine metered-dose inhaler (Primatene Mist), which was taken off the market because it contained a Freon propellant. There is conflicting information in the literature on the relative effectiveness of racepinephrine and albuterol, the most commonly used bronchodilator for asthma.
In an article recently published in The Journal of Allergy and Clinical Immunology: In Practice, Mondal and colleagues report on a pilot study comparing racepinephrine with albuterol for protection against methacholine-induced bronchospasm. Four subjects—18-45 years of age, with mild, stable asthma—completed the study. A methacholine challenge was performed on the first screening day without pre-treatment and then on different days 15 minutes after 1.25 mg albuterol and 2.5, 5, 10, and 20 mg of racepinephrine.
Protection against bronchospasm increased with the dose of racepinephrine, but all doses were less effective than low-dose albuterol. Albuterol was 4 times more effective than 10 mg racepinephrine, which is approximately the non-prescription dose.
In conclusion, racepinephrine provides less protection against methacholine induced bronchospasm than albuterol and thus may be less effective in treating an acute asthma attack.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.