We have investigated 2 serious adverse event cases in young babies who had EMLA (prilocaine/lidocaine cream) applied to their skin for local anaesthesia. Both cases were likely to have involved overdose.
Prilocaine/lidocaine cream (EMLA and various generic brands) is used for topical anaesthesia - to numb the skin - before minor medical procedures.
Overdose of prilocaine/lidocaine can cause serious adverse effects that include methaemoglobinaemia - a condition that reduces the ability of red blood cells to carry oxygen around the body. In severe cases, methaemoglobinaemia can lead to seizures or even death.
Symptoms of methaemoglobinaemia may include headache, dizziness, shortness of breath, nausea, poor muscle coordination and bluish appearance of the skin (cyanosis). Complications may include seizures and irregular heart rhythm.
We have worked with the pharmaceutical companies that supply prilocaine/lidocaine cream to ensure their Product Information, Consumer Medicine Information, product labels and package inserts have adequate appropriate information about the risk of overdose.
What parents and carers should do
Parents and carers should be aware that overdose is possible when applying prilocaine/lidocaine cream to a child’s skin. The overdose risk is particularly high for infants under 3 months and other young children.
You should not use more than the recommended amount of prilocaine/lidocaine cream on a child’s skin, and it should not be left on the skin for longer than the recommended time.
As prilocaine/lidocaine cream is commonly applied before circumcision of young babies, it is important to follow the dosage and application guidelines carefully in that situation. The recommended amount is 1 g applied to the foreskin for a maximum of 1 hour.
What health professionals should do
In general, health professionals should provide clear instructions about using any topical anaesthetic. In the case of use on infants and young children, they should emphasise to parents and carers that using only the recommended amount for the prescribed length of time is essential to prevent potential overdose.
For more detailed information written for health professionals, see this Medicine Safety Update article.