The Irish Medicines Board (IMB) has received 145 reports of adverse reactions to Zyban, the anti-smoking drug. The reactions included dizziness, insomnia, anxiety, nausea, headache and agitation.
To date, two people using Zyban have died in this State but a spokeswoman for the IMB said investigations indicated the deaths were not related to the drug. She said the use of Zyban would be reviewed today and tomorrow at a meeting of a working group of the European Medicines Evaluation Agency. The IMB is a member of the agency and will be represented at the meeting.
Last week, the Medicines Control Agency (MCA) in Britain reported the death of 57 people after suspected adverse reactions to the drug. Some 6,975 reports of suspected adverse reactions were recorded. The MCA emphasised there was no proof that Zyban had contributed to the deaths and that the heavy smoking habits of users may have contributed to the cause.
Zyban was heralded as a breakthrough for smokers wishing to quit when it became available on prescription here in September, 2000. The nicotine-free medicine was initially developed as an anti-depressant until it was noticed that patients had a reduced craving for cigarettes.
However, with concerns over adverse reactions, manufacturers GlaxoSmithKline sent a letter to GPs last summer outlining a modified dosage regime for Zyban and new safety precautions.
The drug is not recommended for people with a history of seizures or certain tumours or for people making an abrupt withdrawal from alcohol or tranquillisers. GPs should have a full medical history of the patient before prescribing the drug, according to the company.
"Appropriate prescribing is the key," said Dr Martina Dempsey, director of medical and regulatory affairs at GlaxoSmithKline. "As with all medicines there is a risk of side effects but, in the case of Zyban, the benefits far outweigh the risks."
Dr Dempsey said the pattern and rate of adverse events was exactly as expected. "Nothing has changed and there are no new safety issues. People are going to die when on medication but that doesn't imply any causal link. We continue to monitor the safety profile of the drug." She pointed out that 50 per cent of smokers died in middle age because of smoking-related disease.
