The court heard that Julie McCabe had visited her doctor between 16 and 20 times over a seven-year period regarding possible reactions to hair dye.
But, although these visits were noted on her record they were never flagged up something that should have been watched out for.
The 38-year-old estate agent lapsed into a coma in October 2011 after using a L’Oreal hair product at her home after a shopping trip with her family.
Just over a year later, in November 2012, she died from heart problems relating to a brain injury.
Her husband, Russell, had been laying out dinner for the family on the day she was struck down.
In a statement at the inquest he said his wife went upstairs to wash the dye out of her hair and moments later he heard her cry “I think I’m going to die.”
Skipton Coroner’s Court heard Mrs McCabe was complaining of struggling for breath and as her husband was preparing to take her to hospital he found her on the driveway “on all fours gasping for breath”.
It was as they were driving to Airedale General Hospital that she lost consciousness.
In a statement read out in court yesterday Mr McCabe, of Keighley, said: “I knew she was in real trouble.”
He added that he was unaware she was allergic to hair dye and believed she was having a severe asthma attack.
The loving mother had complained of allergic reactions at frequent visits to the Crosshills Medical Centre, near Keighley. She also suffered from hay fever and asthma.
Between 2005 and 2011 she was seen up to 20 times for possible hair dye related problems, sometimes suffering from inflamed eyes, rashes and spots.
Doctors at her surgery treated her, mostly with creams, but did not flag her continuing hair dye allergy as something to be wary off – such as with penicillin or peanuts.
Giving evidence yesterday, Dr Sean Emmott said doctors prescribed a betamethasone lotion to treat the symptoms. It was only noted on the day she collapsed at home and was rushed to hospital.
Dr Emmott said: “We would not necessarily record an allergy to hair dye because we do not prescribe hair dye.”
Assistant Coroner Geoff Fell said there was nothing in her notes advising her to stop using the dye. Dr Emmott replied: “It would be stating the obvious to tell her to stop.”
When asked by Sam Harmel, representing Mr McCabe, whether any risk to Mrs McCabe from her allergy was “even on his radar” Dr Emmott replied: “No”.
The inquest continues.