Bridget Mary Kelly, 62, of Station Road, died in the accident and emergency department on February 8 after she was taken to the Conquest by ambulance after suffering breathing difficulties in Tesco car park in Hastings.

Smoker Mrs Kelly, who had serious health problems, died of natural causes, but an A&E doctor admitted that during her treatment he had given her 1 gramme of aminophylline - twice the maximum dosage and four times the recommended starting dosage of 250mg.

Dr Ghassan Youssef told Mrs Kelly's inquest, held at Hastings on Wednesday, that he didn't check the BNF dosage guide before administering the drug, despite having the guide in his hand.

Dr Youssef said: "The patient was very unwell and I was looking after her and another patient at the same time.

"I gave her, at the time, what I thought was the right dosage.

"It was the stress of the situation."

He checked with other members of staff if the drug given 'was ok'.

He added: "It's not unusual to ask two senior nurses about their opinion.

"It's a way of confirming what you know at the time."

When asked by the coroner if he felt someone else had checked for the right dose, Dr Youssef said: "No. I felt that I was sure about the dose."

He added: "Mrs Kelly was in severe distress and I wanted to give her everything I could to improve her condition."

Elaine Shalet criticised Dr Youssef for not personally apologising to the family, including Mrs Kelly's husband Colin, who had been married to Mrs Kelly for 35 years.

She said: "He could have said there and then 'I'm very sorry for doing that' and he never did.

"He had an opportunity to apologise for that error, which is what caused our distress, and he did not."

She added: "It's a very casual way to behave.

"It's not as if the BNF was not available.

"Someone handed it to him.

"It was there to be checked and it could have been checked and it was not."

Mrs Kelly worked at Tesco Express in Battle for nine years before retiring.

More than 200 people attended her funeral in Hastings and more than £1,000 was raised for Guide Dogs for the Blind in memory of the animal-lover.

Mrs Shalet said: "She was a very special person.

"She was very well loved and thought of and always did things for other people."

A spokesperson from the East Sussex Hospitals NHS Trust said: "The trust would like to extend our condolences to the friends and family of Mrs Kelly.

"The coroner heard detailed accounts from all staff involved in respect of the medication prescribed to Mrs Kelly at the time of her admission to Conquest Hospital and he concluded that it was not contributory in any way to the sad death of Mrs Kelly and gave a verdict of death by natural causes.

"The trust took this matter very seriously and conducted an in-depth investigation as soon as the matter was brought to our attention, the conclusion of which has resulted in revised departmental practice and policy."

Coroner Alan Craze record a verdict of death by natural causes.