A systematic review of measures for reducing injection pain during adult immunization

To evaluate the effectiveness of different pain-relieving interventions to reduce pain from immunization in adults.

MEDLINE (1950 to October Week 3 2008) PsycINFO (1967 to December Week 1 2008), CINAHL (1982 to October Week 4 2008), EMBASE (1980 to 2008 Week 43) and the Cochrane Central Register of Controlled Trials (3rd Quarter 2008).

Databases were searched for trials of pharmacological, behavioural, physical or operator-dependant techniques to reduce pain from immunization in adults. The primary outcome was pain as assessed by visual analogue scale or other numeric rating scale.

Six studies representing 853 participants were identified. One study evaluating pharmacological interventions (lidocaine-prilocaine) found them to be effective in reducing pain from immunization. Similarly, two studies evaluating physical pain relieving techniques, either skin cooling interventions (Fluori-Methane) or tactile stimulation (manual pressure at the site of injection) found them to reduce pain. One study of jet injectors found them to be more painful than conventional needle and syringe. Neither freezing needles nor warming vaccines was found to be effective in reducing pain. No studies investigated psychological interventions or oral analgesics (acetaminophen and ibuprofen).

There was limited evidence to support the use of lidocaine-prilocaine, Fluori-Methane and manual pressure for reducing immunization pain in adults. There was limited evidence of more pain with jet injectors compared to needle and syringe. Due to limited data, we recommend further investigation of methods to reduce immunization pain in adults, primarily psychological and physical techniques.