The EpiPen, a pre-filled automated syringe used to treat serious allergic reactions, is the latest example of what happens when the business of medicine meets the altruism of health care.
Mylan, the manufacturer of the EpiPen, has drawn mounting criticism for raising the price of a pair of syringes from $100 in 2007 to $600 today. In response to all the bad press, late last month Mylan announced several cost-saving measures for some patients. And four days later it announced it would produce a generic version of an EpiPen two-pack for $300.
If you’re ever going to need an EpiPen, generic or otherwise, it will most likely be because you’ve had a severe allergic reaction to a particular food, medication, latex item, or insect sting.
What makes stings unique in that group is that everyone who gets stung has a reaction; but what kind of reaction warrants having an EpiPen on hand? (Keep in mind that the primal, flailing, cursing-while-sprinting-away reaction is pure panic psychology and would only be heightened by a shot of epinephrine, a.k.a. adrenaline.)
The initial response to a sting—pain, redness, swelling, itching—is due to a potent brew of chemicals that causes tiny blood vessels to dilate. These chemicals aren’t foreign to our body, and so we don’t become allergic to them.
But venom from stinging insects—most commonly bees, hornets, wasps, yellow jackets, and fire ants—also contains a number of protein enzymes that are foreign to us. And therefore after an initial exposure, our immune system comes to recognize them as allergens.
Here in the U.S., yellow jackets are the most common cause of stings, particularly this time of year, in the late summer and fall. But honeybees are more likely to cause a severe allergic reaction than yellow jackets and the like, which is why Winnie the Pooh shouldn’t have survived to Chapter 3.
The allergic reaction that occurs after a person has become sensitized to a particular venom protein just compounds the red, warm, itchy feeling caused by the initial, nearly instantaneous chemical injury. There are a multitude of factors that determine the strength of that allergic response, but a reaction is officially considered ‘large’ if the welt is bigger than 10 cm.
A revved-up immune response has a certain amount of momentum, so the reaction can expand for 24-48 hours and take 5-10 days to resolve. It can be treated with ice, antihistamines like diphenhydramine (Benadryl), steroid creams, and pain relievers.
A severe allergic reaction—termed anaphylaxis—occurs when the venom stimulates a body-wide activation of the immune system. In the chemical cascade that follows, blood pressure drops, pulse rises, the face and upper airway can swell, and hives and other symptoms can develop.
This is an emergency, requiring a dose of epinephrine and a trip to the ER. Typically, anaphylaxis occurs very quickly after a sting, and the more rapid the onset, the more severe the reaction will likely be. Sometimes a second dose of epinephrine is required a few minutes later if the symptoms were not adequately quelled with the first injection. In a minority of cases (<20%), anaphylactic symptoms can return several hours later, which is why continued observation is important.
So who needs an epinephrine device?
Obviously, anyone who has had an anaphylactic reaction needs to carry one. People who have only had a small local reaction to a sting don’t need one.
People with large local reactions (greater than 4 inches), or children 16 years of age or younger who have had body-wide, skin-only reactions (itching, flushing, hives, and swelling of skin away from the sting site) but no other anaphylactic criteria are still at low risk for developing anaphylaxis. So they can talk with their physician about getting an epinephrine device as a precautionary measure, but it’s not mandatory.
On the other hand, people 17 and older who have experienced body-wide, skin-only symptoms have a 60% chance of developing a full-blown anaphylactic reaction should another sting occur. So they’ll need an allergist and an epinephrine device.
Or, they can pick up the new iPhone 7 Plus-Plus, which comes with an epinephrine auto-injector and a robotic surgical arm that can remove stingers.