A RUNNER from St Mary Bourne has warned of the dangers of overhydration after she fell into a coma having drank too much water.

Johanna Pakenham took part in the 2018 London Marathon but says halfway around she started to feel ill. Beyond that she says she doesn’t remember a thing.

“There’s a little video of me saying to everyone that I feel really wobbly, but I was still talking,” she said. “None of this I remember.”

Johanna continued and eventually finished the race but had to cancel plans for a celebratory meal as she still wasn’t feeling right. Her partner, Richard, took her home but on the way she started to feel worse and worse. Rather than drive the whole way home, they stopped off at a friends’ house on the way.

“I got to a friends’ house and had a seizure,” she said. “I basically almost died on their kitchen floor.”

Johanna was taken via air ambulance to Winchester hospital, and for the following two days says she doesn’t remember a thing.

“On the Tuesday I started talking again, but I don’t remember anything about it all until the evening,” she said.

“Then I woke up and although I remember that, I don’t properly remember what happened. I don’t really recall anything until the Sunday.”

“The days leading up to the marathon I don’t really remember anything.”

Johanna later discovered she had been fallen into a coma after drinking too much water in a short period of time and becoming over-hydrated.

She had been trying to keep herself hydrated on what would go down as the warmest race day in the history of the London marathon.

There were other factors at play. She admits that she hadn’t eaten enough, and also notes that much of her training for the marathon had taken place in the midst of the Beast from the East, and so she wasn’t used to drinking great amounts while running – nor was she used to the running in the 24-degree heat.

“It’s just that I drank too much water,” she said.

“I basically drowned myself by taking on too much water too quickly and not eating.”

Now she is hoping her experience will help to raise awareness of the risks of overhydration.

She says the symptoms of being overhydrated and dehydrated are very similar, and so it can be difficult for people to know whether they need to be drinking more or less.

“I think there should be some kind of understanding of what is a safe amount to drink,” said Johanna.

“There’s so much benefit to drinking water that no one really wants to point out what happens if you drink too much, because it is really rare.”

“My advice would be if you really don’t feel like have a drink of water, don’t drink. You’re supposed to drink a litre-and-a-half a day and unless you’re doing lots of exercise I should think that’s enough.”

“I wouldn’t tell anyone to stop drinking water, goodness me that would be a stupid thing to say. But if you’re going to do exercise just put an electrolyte in your water and that should help.”

Despite her experience, Johanna says she’s not quite finished with marathons. Although this time she’ll be sure to head her own advice and have an electrolyte in her drink.

“I would definitely like to do another one. I’m not saying no,” she said.

“I would like to do another one and actually remember going over the line!”