Casey Stoner says he plans to consult a different physician and see if a change of diet can help resolve the health issue he has struggled with in recent weeks.
The Ducati rider has fallen away from the Yamaha riders in the title battle due to a debilitating condition that has left him exhausted and suffering from stomach cramps in the races.
A string of medical tests after the United States Grand Prix failed to pinpoint a definite cause or solution, and Stoner said he will have the issue investigated further in the break following this weekend's Donington Park race.
"We're going to go and see some more doctors, not so much for different tests, but just to try and get us on a regime and see if a diet can help us," he said. "It's not getting better, it's not changing, and it's very, very frustrating. So we'll see what we can do. It's a nice long break, which we haven't really had so far.
"We've got somebody we consult with who's been very good to us before, Neil Halpin, I've got shoulder surgery done on a recommendation from him and we've always been steered in the right direction. He's not the sort of person who says he's knows what's wrong, he's just trying to figure out what's wrong."
In the meantime he plans to continue limiting his mileage during the Donington Park weekend to conserve energy for the race.
"It's going to stay like that this weekend – the least amount of laps we can do to find a setting, the better," Stoner said. "It worked for us at the Sachsenring and we lasted a little bit longer. At Assen I was dong pretty much full sessions and I was tired before the race. If we continue like this we should be in a better position.
"For some reason I'm already sore today because going out on the bike, but on the bike it felt good. but it's a wet session, it's not hard to ride the bike like this. Concentration level is a lot higher but to ride the bike in general is physically much easier. These last two weekends have been favoring me so I'm happy."