DTaP vaccine causes fewer reactions when given in thighs

A recent study found that children who receive the diphtheria, tetanus and pertussis vaccine in their thigh muscle rather than their arm are half as likely to have a reaction.

The study, which was conducted at the Group Health Research Institute and seven other Vaccine Safety Datalink centers, examined 1.4 million children between the ages of 12 months and 35 months of age. It found that the children who received the DTaP vaccine in their thigh muscle were approximately half as likely to be brought in for medical attention for an injection-site reaction than children who received the vaccine in their arm.

"These local reactions are the most common side effect of vaccinations," Lisa A. Jackson, the study's leader, said. "But we have known relatively little about how to prevent them. Our findings support current recommendations to give intramuscular vaccinations in the thigh for children younger than three years."

Since 2011, the U.S. Advisory Committee on Immunization Practices recommended that intramuscular vaccinations be given to toddlers between 12 months and 35 months in the thigh muscle and to children age three and older in the deltoid muscle of the arm. The researchers found no statistically significant differences between vaccinating in the thigh and arm in the three- to six-year age group.

Prior evaluations of local reactions after the fifth DTaP vaccine in children between four and six years of age determined that vaccination in the thigh was connected to a lower risk of local reactions than vaccination in the arm. Neither ibuprofen nor acetaminophen was found to prevent local reactions following the vaccine.

The study was published in the Monday's online edition of Pediatrics and was supported by the Centers for Disease Control and Prevention through American's Health Insurance Plans.