By Stephanie Stahl

PHILADELPHIA (CBS) — There’s new hope for treating the kind of dementia that doctors say caused actor Robin Williams to take his life. It’s called Lewy Body Dementia and is a mysterious and hard to diagnose disease that’s more common than many realize, afflicting about a million and a half patients.

Treatments have been elusive, until now.

Husband And Wife Charged With Killing Woman’s Stepfather

His hand tremor is part of why Donald Merkel can no longer work on his beloved vintage Corvettes in Horsham. He’s had a hard time staying focused on anything since being diagnosed with Lewy Body Dementia three years ago. His wife Kay says, “he has kept his sense of humor through this whole thing.”

She’s watched the disorder rob Donald’s memory. It also causes hallucinations and Parkinson’s disease which caused the tremors.

Kay says, “it’s devastating really. I’ve always wanted to be a nurse and now I get to be one.” It’s not what they planned, the couple married for 13 years, wanted to enjoy more adventures together. When asked what bothers him most, Don says, “I guess something is being robbed from me, yeah the rest of my life, you know.”

Desperate to hold on, Don is now working with Neurologist David Weisman in Willow Grove, who’s testing a new drug, the first ever developed to treat Lewy Body Dementia. “I’m really encouraged that a drug company is aware of this disease because it’s been way overlooked in the past, and taking this on I think is an exciting first step,” Dr. Weisman says.

The drug is designed to boost neurotransmitters in the brain, to improve memory and reduce other symptoms. Donald says, “hopefully there’ll be a breakthrough which is wishful thinking but you never know, you never know.”

He remembers enough to be emotional about his condition and while hopeful for the drug, Donald doesn’t know if he’s getting it or a placebo. Kay says, “maybe if it doesn’t make a difference for us down the road, it would make a difference for somebody else. I just tell him you have to live every day that God gives us the best that we can.”

The Merkel’s say they’re working hard to stay positive. The drug trial, that’s taking place around the country and here in Willow Grove will last for six months. It’s a double blind investigation which means no one knows who’s getting the real medication. They’re looking for more volunteers to test the treatment.

Stephanie Stahl