Has anyone heard of raw rhubarb making one itch?

The oxalic acid is in the leaves, not the stalks, so you shouldn't have a problem eating the stalks. If you have a reaction a serious reaction, treat it as a poisoning. Call poison control at 800-222-2222: http://www.nlm.nih.gov/medlineplus/ency/article/002479.htm.

Rhubarb & other greens such as Taro leaves contain a large amount of oxalic acid which is store in the cells as Calcium oxalate crystals. Its these crystals which literally embed themselves on the nerve endings giving rise to the itch or irritation when the cell membrane of the rhubarb is punctured upon cutting it. The crystals dissolve in acid which translates to cooking the produce in an acidified water to leach the oxalate out of the cells.

Rhubarb leaves contain high levels of oxalic acid, so they should not be consumed. The stalks are fine and are usually cooked (with sugar as they are so sour otherwise). There are a lot of reports of people having allergic reactions to the raw product.

sdebrango,
I had never touched rhubarb before until that experience, but had eaten it cooked prior to that.

I've read that the leaves are toxic...years ago when my kids were tots there was rhubarb growing behind the garage..we had to fence it off to keep them out.

Its a common allergic reaction to touching rhubarb. I am not sure why you are not allergic to the cooked plant but your syptoms are classic for an allergic reaction. Have you ever touched raw rhubarb before?