Introduction Intravenous paracetamol (actaminophen) has recently been registered for treatment of pain in neonates but the pharmacodynamics, including effects on body temperature, have not been reported.

Methods A pooled analysis on body temperature recordings in neonates exposed to intravenous paracetamol was performed. Body temperature was recorded by skin probe and registered before and every 2 h following initiation of single or repeated intravenous paracetamol administration (up to 48 h). Repeated measures ANOVA and paired analysis were used to quantify differences following paracetamol exposure.

Results The pooled analysis was based on 99 neonates (median weight 2.7 (range 0.5–5.4) kg, median postmenstrual age 37 (range 27–50) weeks). Based on observations in 93 normothermic (<37.8°C) neonates and six neonates with fever, it was documented that paracetamol administration does not affect body temperature in normothermic patients. In neonates with fever, the median decrease (−0.8°C) is most prominent in the first 2 h (p<0.01) following paracetamol administration with subsequent further normalisation.

Conclusions Administration of intravenous paracetamol does not result in hypothermia in normothermic neonates. In those with fever, maximal temperature reduction is achieved within 2 h following paracetamol administration.