London Marathon runner left in a coma after over-hydrating during the race

Image: SWNS 

A runner who fell seriously ill after suffering with hyponatraemia during the London Marathon has shared her story, in an attempt to warn other runners about the danger of over-hydrating.

Johanna Pakenham, aged-53, unknowingly overloaded her body with water whilst taking on the hottest London Marathon on record last month. 

Related: London Marathon 2018 – the stats

According the various news publications, the mum-of-four has no recollection of crossing the finish line, after collapsing at home after the race. Her partner performed CPR to keep her alive whilst waiting for the ambulance to arrive.

Pakenham told newspapers she is sharing her story to warn other runners of the effects of over-hydrating. She said: “I love running and I’ve been doing it for years, I’ve taken part in four marathons – although this was my first one in 15 years. 

“I remember starting the race but around half way through is when things start to get hazy. I saw my family at the beginning and apparently, I saw them three times throughout, but I have no recollection of that.

“I remember my dad’s voice in my head saying ‘make sure you stay hydrated’ but without the electrolytes, the water was doing more harm and making me worse, there is such a thing as too much water, which I learnt.

 

Image: SWNS 

“I had about 400 metres to go and I remember saying ‘I’m wobbly’ and my family couldn’t believe I wasn’t going to cross that finish line.”

 Pakenham crossed the line in six hours 35 minutes, but cannot recall much about the marathon. After collapsing after the race, she was taken to Winchester Hospital, where she was kept in intensive care, in a coma for the days following the race.

Luckily, she has since recovered and is now home with her family.

How do you over-hydrate whilst running? 

By drinking too much water during the marathon, Pakenham sodium levels fell abnormally low, causing a dangerous condition known as hyponatraemia. 

Sodium regulates several important functions in the body, such as the body’s fluid balance and supporting the central nervous system. Hyponatraemia can happen to runners when they over-hydrate on race day and often occurs after four or more hours of running.

Related: The dangers of over-hydrating during a race

Hyponatraemia can cause a number of health issues – some mild, some life-threatening.

 What are the symptoms of hyponatraemia?

As the brain is extremely sensitive to changes in sodium levels, the first symptoms of hyponatraemia will be confusion, dizziness or headaches. Runner’s might also notice their fingers swelling in the early stages of hyponatraemia. Symptoms can also include irritability, muscle weakness, cramping, nausea and vomiting. Dangerous reactions can lead runners to become disorientated, unconscious or experience seizures.

 If you do experience any of these symptoms during a race, or see a runner suffering, seek medical advice immediately. 

Read more: The runner’s guide to hydration