Effect of Methylprednisolone Injection Speed on the Perception of Intramuscular Injection Pain

Abstract 

Pain originating from intramuscular (IM) injection should not be underestimated, because a painful injection might incite severe fear of injection, which may lead a patient to delay seeking medical help. The aim of this study was to determine the impact of two different IM methylprednisolone injection speeds on pain intensity and pain duration. A one-group quasiexperimental design was used to study 10-second versus 30-second injection durations. According to the formula for one sample using average values, 25 patients were recruited from a dermatology clinic. Data were collected using the “Patient Characteristics Form” and the visual analog scale (VAS). The mean difference in pain levels according to the VAS in the postinjection period was significantly higher with administration of IM methylprednisolone in 10 seconds compared with 30-second administration (VAS 1.9 vs. 1.3; p < .05). The severity of pain peaked at 0 minutes for both injection speeds, but the duration of pain was longer with 10-second injections. The data showed that at multiple time points after 10-second injections, men and patients >40 years old experienced greater pain severity. Pain severity after 30-second injections was greater for patients of normal or low weight who had completed higher levels of education. In conclusion, slow IM injection of steroids improves pain management.