The Food and Drug Administration is requiring a new warning and changes to dosing information for promethazine (Phenergan ®), a commonly used drug for nausea and vomiting in children and adults. Phenergan is known to cause breathing to slow down or even to stop, and it is a particular danger in children because children metabolize drugs differently than adults. Although we dose most pediatric drugs by the weight of the child, every child is different and some drugs have more variability from person to person in how they are metabolized. There have now been enough reports of side effects and deaths in children due to phenergan that the FDA is requiring the new warnings and dosing instructions. According to the new warnings:
Phenergan should NOT be used in children less than 2 years of age. Cases of respiratory depression and death have been reported, even at correct weight-based doses, in children less than 2 years old.
“PHENERGAN SHOULD NOT BE USED IN PEDIATRIC PATIENTS LESS THAN 2 YEARS OF AGE BECAUSE OF THE POTENTIAL FOR FATAL RESPIRATORY DEPRESSION. POSTMARKETING CASES OF RESPIRATORY DEPRESSION, INCLUDING FATALITIES, HAVE BEEN REPORTED WITH USE OF PHENERGAN IN PEDIATRIC PATIENTS LESS THAN 2 YEARS OF AGE. A WIDE RANGE OF WEIGHT-BASED DOSES OF PHENERGAN HAVE RESULTED IN RESPIRATORY DEPRESSION IN THESE PATIENTS.”Phenergan should be used with extreme caution in children 2 years of age and older, even when using weight-based dosing, because of the potential for fatal respiratory depression.
“CAUTION SHOULD BE EXERCISED WHEN ADMINISTERING PHENERGAN TABLETS AND SUPPOSITORIES TO PEDIATRIC PATIENTS 2 YEARS OF AGE AND OLDER BECAUSE OF THE POTENTIAL FOR FATAL RESPIRATORY DEPRESSION. RESPIRATORY DEPRESSION AND APNEA, SOMETIMES ASSOCIATED WITH DEATH, ARE STRONGLY ASSOCIATED WITH PROMETHAZINE PRODUCTS AND ARE NOT DIRECTLY RELATED TO INDIVIDUALIZED WEIGHT-BASED DOSING, WHICH MIGHT OTHERWISE PERMIT SAFE ADMINISTRATION.”Phenergan (as well as other anti-vomiting medications) is NOT recommended for the routine treatment of vomiting in pediatric patients, due to the dangerous side effects. Not only can it cause breathing to stop, it can also cause confusion and mental status changes which can make accurate diagnosis and treatment of the child extremely difficult.
“ANTIEMETICS ARE NOT RECOMMENDED FOR TREATMENT OF UNCOMPLICATED VOMITING IN PEDIATRIC PATIENTS, AND THEIR USE SHOULD BE LIMITED TO PROLONGED VOMITING OF KNOWN ETIOLOGY.”
These warnings and dosing changes do not really represent a change in our practice. These side effects and dangers have been known for years. I avoid using phenergan in young children, and use it only sparingly in older children. Often when I prescribe it I am doing so at the parent’s insistence. Parents should be aware of the potential dangers of Phenergan and avoid using it unless absolutely necessary, if the benefits outweigh the risks. I think it is generally a safe drug when used sparingly and appropriately, at a correct dose, in older children and adults.
