Trial design and protocol of randomized controlled trial comparing the efficacy of oral mefenamic acid, paracetamol and placebo for analgesic prophylaxis in childhood vaccination (MAP VaC trial)


  • Rachna Pasi Department of Pediatrics, All India Institute of Medical Sciences (AIIMS), Mangalagiri, Andhra Pradesh, India
  • Thirunavukkarasu Arun Babu Department of Pediatrics, All India Institute of Medical Sciences (AIIMS), Mangalagiri, Andhra Pradesh, India
  • Vinoth Kumar Kallidoss Department of Community and Family Medicine, All India Institute of Medical Sciences (AIIMS), Mangalagiri, Andhra Pradesh, India



Immunization, Needle pain, FLACC scoring, Analgesics


Background: Needle related pain has been one of the most important concerns for parents of children receiving vaccination. Non-steroidal anti-inflammatory drugs (NSAIDs) like paracetamol and mefenamic acid have been commonly used as analgesics in pediatric population. However, prophylactic administration of these drugs for analgesia during vaccination has not been studied. The main objective of this study is to compare the efficacy of prophylactic paracetamol, mefenamic acid and placebo on needle pain associated with vaccination.

Methods: This is a three-arm parallel, triple blind, randomized controlled trial. Children aged 6 weeks to 7 years who need immunization as per national immunization schedule and reporting to pediatric outpatient department (OPD) at tertiary level hospital, AIIMS Mangalagiri, Andhra Pradesh, will be included. All participants will be randomly allotted to any of the three groups by computer based block randomization. Each participant will be given any one of the three drugs as per their allocation. Vaccination will be done as per national immunization schedule after 30 minutes of drug administration. Face, legs, activity, cry, consolability (FLACC) scoring will be done immediately after vaccine administration and repeated at 15 minutes and 30 minutes. All personnel involved in randomization, drug and vaccine administration, FLACC scoring and statistical analysis will be blinded along with parents and children enrolled in the study.

Conclusions: If this intervention study shows evidence of a difference between drug and placebo signifying reduction in vaccine related pain with these drugs, this will have a huge impact on National Immunization programme by improving compliance, vaccine coverage and by reducing vaccine hesitancy.

Trial registration: Clinical trials registration number is CTRI/2021/01/030239.

Author Biography

Rachna Pasi, Department of Pediatrics, All India Institute of Medical Sciences (AIIMS), Mangalagiri, Andhra Pradesh, India

Assistant Professor, Department of Pediatrics


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