Undiagnosed hay fever sent fit and healthy woman into cardiac arrest

This Morning's resident soap expert Sharon Marshall explained that she almost died from undiagnosed hay fever which left her struggling to breathe.

Appearing on the sofa today (25 March), she explained that one year her breathing started 'getting worse and worse' until she woke up in the middle of the night and 'just couldn't breathe'.

"I didn't know at that time that that was an asthma attack because I'd never had one before and I didn't know that that I had it," she told the show.

"But it was utterly terrifying, and you can't think straight when you can't get a full breath."

Sharon explained that she waited for several hours for the doctor's surgery to open and then told her 'come in immediately', with her getting a black cab.

Sharon Marshall was left barely able to breathe and told she was going into cardiac arrest in the back of an ambulance (Joe Maher/Getty Images for the NTA's)

However, she doesn't remember much after arriving at the surgery because after the taxi driver helped her get inside she collapsed.

"I came round in the back of an ambulance and I was a bit ‘what's happening’ and they said, ‘we're taking you to hospital’.

"My first reaction was, ‘oh, will I be going back?’ and they said, ‘Well, no, probably not.’ I said, ‘Can I go and stop and can I just go by the house and feed my cat?’

"I remember this lovely guy who was just saying, ‘You're going into cardiac arrest. We're trying to take you to hospital to save your life. No, you can't feed your cat.’"

Fortunately a neighbour fed the cat, but unfortunately for Sharon she spent a week in hospital and doctors weren't able to work out what was wrong with her.

She said they 'saved her life', but afterwards told her she needed to stop smoking and she had to explain she wasn't a smoker.

Eventually they diagnosed her with adult onset asthma and for several years she was using inhalers to treat her breathing.

Each Spring she would get worse again, though the timing wasn't connected with hay fever, and even as she was 'on the strongest asthma inhalers' she would be getting through an inhaler set in a week.

She said: "Every spring I started getting really breathless and really ill and I would go to the doctors and, again this isn't a criticism of the NHS, they're seeing a lot of patients and they’re only seeing you for 10 minutes.

“But I'd be going ‘three weeks ago I was running 5K around the park no problems, now I literally can't’.

"I remember the doctor's surgery was up this flight of stairs. I could only get up five steps and I'd be breathless and they would have to come down and see me."

In an effort to work out what was happening to Sharon they even sent her for lung cancer scans.

She only found out what was wrong with her after Professor Adam Fox appeared on This Morning and connected her illness to the time of year (ITV)

She only found out what was wrong when she had an asthma attack while getting ready for a segment on This Morning, having been 'outside for 20 seconds' on her way into the studio.

Sharon was in makeup when she 'realised she couldn't get to the end of the sentence'.

Fortunately, allergy specialist Professor Adam Fox was on the show who was able to put things together that her problems were happening at a particular time of the year.

She now takes Itulazax, an immunotherapy tablet to treat birch tree pollen allergy, which she said had been 'miraculous' for her.

Her condition improved to the point she was told to try stopping her asthma inhalers, and though she initially said 'these the only things keeping me alive' she tried it and has since gone from being on the strongest possible dose to not taking them for three years.

She said: "The comparison of I can't walk outside and I can't go up five stairs without fearing an asthma attack.

"It means I'm not scared of Summer anymore. I can go outside with my daughter. I’d be terrified every Spring, like is a tree going to kill me? It’s life changing."