Non-pen-like functionality causes needle stick injuries

Some other auto-injectors are designed like upside-down ball-point pens. The end where the needle emerges can be confused with the activation button, as on a pen.1 In the back there is also a second hole which can be confused as being the needle exit. Patients turn their auto-injector the wrong way leading to needle stick injury.2-3

Education and training on the use of the auto-injector is important. Training can however not compensate for a poor product design.4

Human-factor engineer L.L. Gosbee explains: “Each time their tendency is to push the top end of the auto-injector as if they were activating a ball-point pen. They instinctively do it even with previous training. I try to remind them: It does not work like a pen!” 4

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  1. Madsen, P.L., Matsson, N., Some auto-injection pens are counterintuitive. BMJ, 2009. 338: p. b1303.
  2. Simons, F.E.R., Lieberman, P.L., Read, E.J., and Edwards, E.S., Hazards of unintentional injection of epinephrine from autoinjectors: a systematic review. Ann Allergy Asthma Immunol, 2009. 102: p. 282-7.
  3. Simons FE, Edwards ES, Read EJ Jr et al. Voluntarily reported unintentional injections from epinephrine auto-injectors. J Allergy Clin Immunol 2010;125(2):419–423.
  4. Gosbee, L.L., Nuts! I can’t figure out how to use my life-saving epinephrine auto-injector! Jt Comm J Qual Saf., 2004. 30(4): p. 220-3.