Sublingual vs Intramuscular Epinephrine
Rawas-Qalaji MM, Simons FER, Simons KJ
J Allergy Clin Immunol. 2006;117:398-403
Anaphylactic reactions usually occur in an unexpected and frightening manner, and may result from exquisite allergic sensitivity to foods, drugs, stinging insects, natural rubber latex, as well as other triggers. Prompt recognition of the symptoms of anaphylaxis is of paramount importance, followed by timely treatment with injected epinephrine. As these authors from Canada point out, there is universal agreement that the treatment of choice for anaphylaxis is prompt injection of epinephrine.
Despite its life-saving potential, self-injection of epinephrine is underused in the community. Some patients are hesitant to inject themselves with a needle, even when it is clear that they need to do so in a medical emergency. The cost of autoinjectors may also be a barrier to more widespread availability and use worldwide.
Research into alternative strategies to treat anaphylaxis in humans is difficult for a number of reasons. By its very nature, anaphylaxis is rare and unpredictable, making controlled trials of various treatment alternatives nearly impossible, and it is ethically unacceptable to subject a patient with a potentially life-threatening reaction to a possible treatment alternative that may not be effective. Therefore, the investigators of this study used a prospective 5-way crossover study with a validated rabbit model, studied various doses of a new, fast-dissolving sublingual epinephrine tablet, and compared serum concentrations after sublingual epinephrine with 0.3 mg intramuscular epinephrine delivered with an autoinjector. Serum concentrations were measured using high pressure liquid chromatography at various time points, ranging from the time of injection up to 180 minutes after the injection.
The results showed that 40 mg of sublingual epinephrine was required to produce comparable serum concentrations produced with 0.3 mg of intramuscular epinephrine. They noted that injected epinephrine is underused in the community, and that this novel sublingual epinephrine formulation may provide a viable option for management of anaphylaxis in some patients in the future.
With our current level of knowledge, epinephrine tablets are not an appropriate alternative to injected epinephrine, if injected epinephrine is available. For a patient with a history of anaphylactic shock to foods, stinging insects, latex, or another substance, the appropriate treatment plan would be to prescribe injectable epinephrine. If and when quick-dissolving epinephrine tablets become available for sublingual administration, they may prove to be a helpful option when autoinjectors are not available, not preferred, or not affordable. This potential new form of treatment deserves close attention as it receives further evaluation and testing.
Abstract
Rawas-Qalaji MM, Simons FER, Simons KJ
J Allergy Clin Immunol. 2006;117:398-403
Anaphylactic reactions usually occur in an unexpected and frightening manner, and may result from exquisite allergic sensitivity to foods, drugs, stinging insects, natural rubber latex, as well as other triggers. Prompt recognition of the symptoms of anaphylaxis is of paramount importance, followed by timely treatment with injected epinephrine. As these authors from Canada point out, there is universal agreement that the treatment of choice for anaphylaxis is prompt injection of epinephrine.
Despite its life-saving potential, self-injection of epinephrine is underused in the community. Some patients are hesitant to inject themselves with a needle, even when it is clear that they need to do so in a medical emergency. The cost of autoinjectors may also be a barrier to more widespread availability and use worldwide.
Research into alternative strategies to treat anaphylaxis in humans is difficult for a number of reasons. By its very nature, anaphylaxis is rare and unpredictable, making controlled trials of various treatment alternatives nearly impossible, and it is ethically unacceptable to subject a patient with a potentially life-threatening reaction to a possible treatment alternative that may not be effective. Therefore, the investigators of this study used a prospective 5-way crossover study with a validated rabbit model, studied various doses of a new, fast-dissolving sublingual epinephrine tablet, and compared serum concentrations after sublingual epinephrine with 0.3 mg intramuscular epinephrine delivered with an autoinjector. Serum concentrations were measured using high pressure liquid chromatography at various time points, ranging from the time of injection up to 180 minutes after the injection.
The results showed that 40 mg of sublingual epinephrine was required to produce comparable serum concentrations produced with 0.3 mg of intramuscular epinephrine. They noted that injected epinephrine is underused in the community, and that this novel sublingual epinephrine formulation may provide a viable option for management of anaphylaxis in some patients in the future.
With our current level of knowledge, epinephrine tablets are not an appropriate alternative to injected epinephrine, if injected epinephrine is available. For a patient with a history of anaphylactic shock to foods, stinging insects, latex, or another substance, the appropriate treatment plan would be to prescribe injectable epinephrine. If and when quick-dissolving epinephrine tablets become available for sublingual administration, they may prove to be a helpful option when autoinjectors are not available, not preferred, or not affordable. This potential new form of treatment deserves close attention as it receives further evaluation and testing.
Abstract