Zyban is used in a population of patients who are put at risk because of smoking and, therefore, reports of deaths are to be expected

Professor Alasdair Breckenridge, Committee on the Safety of Medicines

Parents Eddie and Eileen Weston described how their daughter had suffered a suspected seizure and complained of blackouts and a headache after she started taking Zyban.

Eileen Weston said Kerry had felt unwell on her return from a flight to Baltimore on 13 January.

"She told me she had got ready to report for the flight and meet the rest of the queue in the foyer of the hotel.

"She remembered feeling unwell and then all she remembered was waking up on the bathroom floor as if she had gone to sleep.

"Her words were that she thought she had fallen asleep in the bathroom but her head was very sore when she stood up."

Great concern

Mr Weston told the inquest that he was so concerned by his daughter's apparent blackout that he immediately took her to Hertford Emergency Medical Centre.

The doctor at the clinic noted she had a lower than normal temperature, her eyes were red and that she had a slight bump on her head.

Maggie Gilliland, cabin service director on Kerry's final flight from Gatwick, described how her colleague had looked very pale when they arrived at the stop-over hotel. However, she insisted that she was just very tired.

Ms Gilliland and a colleague found Kerry dead in her room later that evening.

GP Dr Mark Andrews told the inquest Kerry had asked for help to curb a 15-a-day habit during a visit to the surgery on 3 January this year.

He said he had discussed the possible side effects of Zyban before deciding to prescribe it for Kerry. Although he had asked whether she had suffered seizures in the past, he had not checked her medical records.

Other deaths

Dr Howard Marsh, of pharmaceutical giant GlaxoSmithKline, which manufactures Zyban, revealed that there had been more than 30 deaths following adverse reactions to the drug.

But he said: "Although there has been this number of reports of fatal events it has to be said these are suspected adverse reactions.

"The contribution of Zyban to any of them remains unproven."

Dr Marsh said many of the deaths were believed to be from smoking-related diseases and some had occurred in people who had stopped taking the drug weeks beforehand.

He said Zyban should not be used by people with a history of seizures or epilepsy, people with liver disease or people with manic depression.

Fits risk

There was a one in 1,000 risk of people suffering fits as a result of taking Zyban, he added.

But he admitted that the anti-malarial treatment Kerry had been taking may have increased the risk.

Zyban has been used by more than 360,000 people in Britain since the treatment was introduced last year.

The drug has been hailed as a major breakthrough in helping smokers to beat their addiction.

In clinical trials a third of people taking the prescription pills had managed to kick the habit for more than a year, making it twice as effective as nicotine patches.

The drug acts on the brain to quash the craving for nicotine that tobacco produces.

Professor Alasdair Breckenridge, chairman of the Committee on the Safety of Medicines, said: "Zyban is used in a population of patients who are put at risk because of smoking and, therefore, reports of deaths of patients receiving Zyban are to be expected.

"Where information is available, the majority of patients who died had underlying conditions that provide an alternative explanation."

He pointed out that about 2% of adverse reports for all medicines result in the death of patients.

For Zyban, the proportion of fatalities is much lower, at about 1% of all adverse reports.

The inquest continues.