The goal of this paper is to conduct a literature review on the clinical consequences of epinephrine auto-injector needle length. Within 10 minutes of intramuscular injection into the thigh, epinephrine has the greatest pharmacodynamic impact. Prefilled epinephrine auto-injectors are made for ease of usage and safety. In situations of anaphylaxis, patients generally utilize auto-injectors in an unsupervised setting. To avoid dosage mistakes, weight-appropriate epinephrine doses of 0.15, 0.30, and 0.50 mg are provided with prefilled auto-injectors. Furthermore, needle lengths range from 1.17 to 2.50 cm. The needle lengths suggested for adults and pediatric patients varies. Furthermore, needle lengths vary between devices. Concerns have been raised that the needle length may be too short in some obese people. However, there are concerns that the needle length in certain individuals may be excessively lengthy. Not only does the needle length impact the depth of the injection and hence the pharmacokinetics of the medication, but so do BMI, obesity, soft tissue compression, and propulsion.

The needle length of epinephrine auto-injectors varies. Using the suitable device with the appropriate needle length depending on BMI and obesity, as well as applying the proper technique, can enhance the result of an anaphylactic episode.