The woman suffered 15 wasp stings during the attack.

A woman being treated for wasp stings says she screamed in pain at the intravenous infusion into her left hand of a medicine which a review suggests was not needed.

The woman had disturbed a wasp nest and been stung up to 15 times on her face, neck and right arm in March last year, according to a report by Deputy Health and Disability Commissioner Theo Baker, which conceals the names of the parties.

The woman went to a pharmacy and was given Telfast, an antihistamine tablet. She proceeded to an accident and medical clinic, where a doctor noted she did not have low blood pressure, asthma or throat swelling and prescribed intravenous (IV) promethazine and hydrocortisone.

He chose promethazine, an antihistamine, to prevent potentially-fatal anaphylaxis, because she had a history of "severe and prolonged swelling after a single previous sting".

Promethazine is highly caustic and is meant to be diluted ten-fold with water before intravenous use because of the risk of vein inflammation.

The nurse gave the woman undiluted promethazine, which Ms Baker judged a breach of the code of patients' rights and led to her recommendation the nurse undertake training on IV drugs.

The woman became drowsy, a recognised side effect of promethazine, soon after the infusion began and could not be roused. She was taken to a hospital by ambulance and was discharged the next day. She was later diagnosed with vein inflammation and suffered weakness in her left arm, which became swollen and painful if she knocked it.

The patient told the commissioner's office of the infusion,

"... I was crying, with my face screwed up saying it's burning and stop! I'm not sure what else she [the nurse] expected from someone to alert her it was intolerable ..."

The nurse said that although the woman had stated that the infusion was tender, she did not ask her to stop.

Ms Baker said she was not sufficiently persuaded the woman sought a halt.

The deputy commissioner's medical adviser, Dr David Maplesden, said the doctor's diagnosis was unclear, but the woman did not appear to be in anaphylaxis. It was likely she was suffering a mild to moderate allergic reaction, for which the oral antihistamine was the proper treatment.

Dr Maplesden was not convinced IV promethazine was the right course. If the doctor had truly felt her life was potentially at risk, as he had stated, the woman should have been given intramuscular adrenaline.

He said there was some confusion in the use of adrenaline and antihistamines and although the doctor's care of the woman was inconsistent with best practice, "it was consistent with common practice".

Medsafe had added to the confusion: its apparent acceptance that IV promethazine could be used in emergencies such as treatment of anaphylaxis seemed inconsistent with current evidence and contradicted Australian guidelines.

Medsafe told the Herald it would review Dr Maplesden's comments about the promethazine datasheet and the Australian guidelines.

 

By Martin Johnston