Ukraine Candidate Poisoned?

Can any of our medical dopers shed some light on this? A number of news outlets have talked about the dramatic change in appearance of Ukranian PM candidate Viktor Yushchenko. If you just look at the pics, it’s absolutely shocking.
Other photos of him don’t look quite as bad, but I don’t know if that means he’s improving or if it’s just a question of lighting and makeup.

He says he was poisoned. Doctors have said that’s possible but it could also be stress-related. What kind of poison or ailment would do that to his face? On another note, has anybody followed this election closely enough to know if his appearance changed out of the blue, or if it was a little more gradual?

This was discussed in a recent thread, so I’ll close this one and direct further comment to the earlier one: What happened to Viktor Yushchenko’s face?

bibliophage
moderator GQ