A WOMAN battling a rare muscle weakening disease is gearing up for a mammoth two-day trek around the London Marathon course.

Sara Lloyd-Williams has suffered double vision, extreme weakness all over her body, and swallowing and breathing difficulties, caused by the incurable illness Myasthenia Gravis (MG).

The sometimes fatal disease is caused by the body’s immune system attacking and damaging the nerve signal areas on muscle and affects only about 5,000 people in the country.

However, thanks to the care of doctors in Oxford, Miss Lloyd-Williams, 35, is over the worst and preparing to walk the 26.2 mile route through London to help fund research into a cure.

She will join hundreds of other sufferers in the ‘Why Run When You Can Walk’ event on Saturday, April 17, and Sunday, April 18, with by her son Samuel, three, in his pushchair.

Miss Lloyd-Williams, of Shilton Park, Carterton, began noticing double vision in January 2005 and her optician referred her to hospital.

She said: “It was horrendous, I got mistaken for being drunk because I slurred my words, had double vision and wore an eye patch. I couldn’t walk up and down the street.

“I had to have my food puréed and drinks thickened. You lose control and people look at you and think, two hours ago you were quite healthy.

“You can wake up in the morning and feel really okay, but as the day progresses you feel weaker and weaker.

“My speech was terrible, it was like I’d had 20 pints. It’s incredibly frightening.”

The condition began to affect her breathing and she was rushed to hospital, staying for two weeks while doctors got to the bottom of the problem.

Miss Lloyd-Williams, who works for Oxfordshire County Council, was diagnosed with MG in March 2005.

She had white blood cell transfusions and took up to 30 pills a day.

She said: “I didn’t realise how ill I was because you develop your own coping method. I’d learned to do things differently.

“It wasn’t fully under control until 2007. ”

With a pedometer and the pushchair, Miss Lloyd Williams is confident she will reach the finish line.

She said: “It’s a massive challenge for me because when I’m unwell I can’t walk to the car park, never mind 26.2 miles.”

See our first round-up of county marathon in runners in tomorrow’s Oxford Mail.