The Therapeutic Goods Administration has ruled that the popular allergy medicine Phenergan should not be given to children under six years of age.

Following an investigation, the TGA said it was updating its advice on the drug “to include the risks of psychiatric and central nervous system side-effects in children under six, including hyperactivity, aggression and hallucination”.

When high doses of the over-the-counter drug are given, children at risk “may also experience difficulties in learning and understanding, such as reversible cognitive deficit and intellectual disability”.

In a Conversation report on the update, the pharmaceutical and pharmacology expert authors further warned:

“Breathing can also become slow or shallow, which can be fatal.”

In 2015, the Australian Medical Association advised parents not to use drugs such as the antihistamine Phenergan to sedate their children during long road trips or flights.

The AMA warned: “Ten per cent of children who are given Phenergan have a paradoxical response and rather than getting a little bit sleepy or drowsy it ramps them up and they get hyperactive.”

What is Phenergan?

Phenergan is the best known version of the oral antihistamine promethazine hydrochloride.

The registered therapeutic indications (reasons for use) for Phenergan are:

• Allergic reactions. These include hives, insect bites and stings,  contact dermatitis, and reactions to drugs
• Relief (drying up) of secretions as a result of hayfever and llergic rhinitis
• Nausea and vomiting. These include post-operative vomiting, irradiation sickness, drug-induced nausea and motion sickness
• Sedation, short-term, under the advice of a doctor or pharmacist. Do not use for more than seven to 10 consecutive days.

These sedative effects can be used in the symptomatic management of measles and chicken pox.

The TGA said there are almost 50 other brands of oral promethazine hydrochloride on the Australian market. These brands will be required to update their product information and labelling.

Oral promethazine products are currently scheduled S3, which means they can be sold over-the-counter with advice from a pharmacist.

The TGA expects “there will be a time lag before all products available in pharmacies will have updated package labelling”.

The safety advice, however, should be adopted immediately.

What to use instead

The authors of the Conversation report – who are experts in pharmaceutical chemistry and pharmacology – suggest that for allergies or hay fever in young children, non-sedating antihistamines such as Claratyne (loratadine) or Zyrtec (cetirizine) are preferred.

For cold or cough symptoms, parents should allow the complaint to run its course unmedicated, while keeping up fluids and ensuring plenty of rest. 

For congestion from hayfever use saline nasal sprays, hydration, a humidifier, or elevate the child’s head.

Oral phenylephrine products, marketed for nasal congestion, should be avoided. “Evidence shows they are ineffective, but nasal spray formulations of the drug are fine to use,” the article wrote.

For fever or discomfort, “paracetamol remains a safer choice”.