Updated

The first skin patch to treat the dementia that can plague Alzheimer's patients gained federal approval, a drug company said Monday.

The drug in the patch, called Exelon or rivastigmine, is the same as that now available in capsule form but provides a regular and continuous dose throughout the day, according to Novartis Pharmaceuticals Corp. Since the drug enters the bloodstream directly, the patch also eliminates some of the gastrointestinal side effects associated with the drug when swallowed.

The drug is meant to treat the symptoms of mild to moderate dementia in patients with Alzheimer's disease. It also won Food and Drug Administration approval to treat patients with mild to moderate Parkinson's disease dementia, Novartis said.

About 4.5 million Americans have Alzheimer's. As the disease progresses, it robs patients of their memories and changes how they both think and behave. It's ultimately fatal.

Rivastigmine isn't a cure. It inhibits the breakdown of a chemical in the brain called acetylcholine, thought important for both learning and memory.

Novartis said the prescription patch would be available soon.

The patch is made by Germany's LTS Lohmann Therapie-Systeme AG and distributed by Novartis Pharmaceuticals, part of Switzerland's Novartis AG.

Patch Fact Sheet:

— Can also treat patients with mild to moderate Parkinson's disease dementia

— Provides regular and continuous dose throughout the day

— Eliminates some gastrointestinal side effects linked to drug when swallowed

— Treats symptoms of mild to moderate dementia

— Inhibits breakdown of acetylcholine, brain chemical thought important for learning and memory

— About 4.5 million Americans have Alzheimer's