Acetaminophen Before Vaccines for Infants Study (AVIS)

A Randomized Placebo-controlled Trial of Acetaminophen for Prevention of Post-vaccination Fever in Infants

The purpose of this study is to see whether giving acetaminophen (the medicine in Tylenol) for routine infant vaccinations is helpful in preventing fever or other symptoms.

Post-vaccination fever occurs in up to 40% of infants receiving routinely recommended childhood vaccinations. Although serious events are rare, post-vaccination fever causes discomfort for the child, can lead to medical utilization, can rarely result in febrile seizure, and can cause a working parent to miss time from their job to care for a febrile infant who cannot attend day care. The benefits of acetaminophen prophylaxis for infants receiving current vaccinations, in terms of reduction of discomfort for the child, improvement of quality-of-life indicators for the parent, or reduction of medical utilization, have not been measured. This randomized, blinded, placebo-controlled trial will assess the efficacy of prophylaxis with acetaminophen in prevention of fever following routine childhood immunizations.

Children were randomized 1:1 to receive up to five doses of acetaminophen (10-15mg per kg) or placebo following routine vaccinations.

Children were randomized 1:1 to receive up to five doses of acetaminophen (10-15mg per kg) or placebo following routine vaccinations.

Children were randomized 1:1 to receive up to five doses of acetaminophen (10-15mg per kg) or placebo following routine vaccinations.

Children were randomized 1:1 to receive up to five doses of acetaminophen (10-15mg per kg) or placebo following routine vaccinations.

Telephone calls to the consulting nurse or the child's physician that were made due to concerns regarding an acute illness, fever, or possible vaccine reaction and outpatient, urgent care, and emergency room visits that were for evaluation of an acute illness, fever, or a possible vaccine reaction, within 32 hours of vaccination.

Parents were asked to record level of fussiness (compared with the child's usual) within 32 hours of vaccination, using the categories much less than usual, less than usual, about usual, more than usual, and much more than usual.

Parents were asked about their sleep on the night following the vaccinations. They were asked to report whether they slept much less than usual, less than usual, about the usual amount, more than usual, or much more than usual on that night.

Parents were asked about their infant's sleep on the night following the vaccinations. They were asked to report whether their infant slept much less than usual, less than usual, about the usual amount, more than usual, or much more than usual on that night.

Parents were asked to report whether they were scheduled to work on the day of the vaccination visit (but following that visit) or the next day and, if so, whether they had to miss work to care for their infant because of fever, fussiness, or possible vaccine reaction on those days.

Inclusion Criteria: Child is a current Group Health enrollee. Child will be seen at a Group Health clinic for a Well Child visit that is expected to include 2 or more vaccines after 6 wks and before 10 months of age. Exclusion Criteria: If child was born at less than 36 weeks of gestation, the child is not eligible until 4 months of age or older. If the child's birth weight was less than 5.5 pounds (2500 grams), the child is not eligible until 4 months of age or older.

Jackson LA, Peterson D, Dunn J, Hambidge SJ, Dunstan M, Starkovich P, Yu O, Benoit J, Dominguez-Islas CP, Carste B, Benson P, Nelson JC. A randomized placebo-controlled trial of acetaminophen for prevention of post-vaccination fever in infants. PLoS One. 2011;6(6):e20102. doi: 10.1371/journal.pone.0020102. Epub 2011 Jun 17.