Relief of MMR vaccination pain using topical 4% amethocaine

Routine vaccinations are the most common source of iatrogenic pain in infants and children, however this pain is not routinely managed. 4% amethocaine gel is a new anaesthetic agent that achieves anaesthesia within 30-45 minutes of application; this shortened application time may make its use feasible in busy clinical settings. The objective of this study was to determine the efficacy and safety of 4% amethocaine for reducing the pain of measles-mumps-rubella (MMR) vaccination. A randomized, double-blind, placebo-controlled design was employed. Healthy 1 year old infants receiving their routine 12-month MMR vaccination were recruited and randomized to receive 1g of amethocaine or a visually identical placebo for 30 minutes prior to vaccination. The vaccination procedure was videotaped and the tape used later for pain assessment. The Modified Behavioural Pain Scale (MBPS) was the primary outcome measure for pain. A 5–mL sample of blood was collected from infants 1 month post-vaccination to assess antibody titers using enzyme immunoassay. The amethocaine group (n = 61) had significantly lower pain scores than the placebo group (n = 59); 1.51 vs. 2.29 (p=0.029). There was no difference in antibody response between the amethocaine and placebo treatment groups(p<0.05). Amethocaine reduced the pain of MMR vaccination without compromisng the immunogenicity of the vaccine. Clinical Pharmacology & Therapeutics (2004) 75, P75–P75; doi: 10.1016/j.clpt.2003.11.285