The EpiPen® auto-injector contains epinephrine, used during an emergency to treat severe allergic reactions, or anaphylaxis.
If one is allergic to an insect or food, a severe allergic reaction may ensue upon exposure, in which the immune system releases a flood of chemicals that can cause throat tightness, hives, lip and facial swelling, difficulty breathing, nausea, vomiting, low blood pressure, rapid heart rate, cardiac arrest and possibly death.
Epinephrine stimulates the heart to increase cardiac muscle contractility, cardiac output, subsequently raising the blood pressure. Additionally it relaxes the muscles surrounding the airways, allowing one to breathe easier and take in more oxygen. Moreover it helps to stop the release of additional immune chemicals.
The EpiPen® is manufactured by Mylan. Its cost made headlines when the EpiPen two-pack recently stickered for close to $600. Now generic forms are available costing anywhere from $109-$300 for a dual pack.
The disposable auto-injector, for an adult, delivers 0.3 mg of epinephrine, while the EpiPen Jr., used in pediatric populations, delivers 0.15mg of the medication. It can be self-administered, through clothing if necessary, into the thigh muscle in one smooth movement once the safety release is removed.
After 0.3 ml is administered during the single adult dose, the EpiPen® unit is discarded.
However many are not aware that 1.7 ml of solution remains within the cartridge. This could, in theory, be used for an additional 5 doses if in a remote, “wilderness” setting.
Dr. Arthur (Tony) Islas, Fellow of the Academy of Wilderness Medicine, and professor at the University of Nevada, Reno School of Medicine’s Department of Family Medicine, demonstrated how to extract the remaining doses from the autoinjector at the January Nevada Academy of Family Physicians meeting in Lake Tahoe.
Although it's recommended that all users follow the manufacturer’s labels, those trained in emergency and wilderness medicine may take the used cartridge, cut off the top plastic, and extract the syringe with the remaining fluid.
Dr. Islas states the initial 0.3 mg dose of epinephrine lasts for 20 minutes. For most people this allows plenty of time for emergency responders to come to the site of the victim. However, in a “wilderness” or remote setting, another dose may need to be administered during a very severe case of anaphylaxis.