Last night my mom brought out some Capzasin cream (in the red tube) and asked me to rub it on her arthritic arm and shoulder. She warned me to be sure to wash my hands immediately after applying it because it is VERY HOT (not temperature-hot, but the active ingredient comes from chili peppers), she'd put some on, then rubbed her eye and it burned for a long time. I put the stuff on all up and down her arm and shoulder, then washed my hands thoroughly with soap and water. She was right: for about half an hour afterward the palm of my hand that I'd used to apply the stuff felt hot and tingly. Eventually the heat subsided a bit, and after while I took my nightly bath. Well, I ran the water hot, and when I dunked my hand in the hot water, that reactivated the Capzasin residue and my hand again felt hot. I slept ok, and by morning I couldn't feel the heat, but after I took my morning shower, washed hands etc., again the palm burned for a while. It seems finally to have let up, and when I Googled "capsaicin" (the name of the active ingredient) I found that it's water-insoluble. I think I read somewhere (a long time ago) what it's soluble in, but can't remember what it was. Can anybody offer a suggestion?
Alcohol does work to a degree - the higher the proof, the more it works (but you can't put alcohol in your eyes, so you just have to wait out the burn if it gets in your eyes). There is no 100% quickly-acting effective neutralizer that I'm aware of. The best solution is preventative- use rubber/latex gloves or some other skin barrier when applying (and in my experience the very thin latex gloves don't provide much protection. I've used latex gloves to cut peppers, and have felt the burn through the gloves. Now whether the gloves had microscopic tears that I didn't see, or whether the capsaicin ate through the latex I couldn't tell you.
Personally I find that a thick sponge or wadded up wash cloth provides better protection than most golves, as long as you make sure that your hands don't come in direct contact with the cream.
You also have to be aware of the potential for second-hand contact (the cream rubs off onto your sheets, you touch the sheet and then rub your eye).
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