Pain-relieving creams

When used as directed, methyl salicylate, the chemical in topical pain relievers causes a warming sensation and helps dull muscle aches; but if used in high doses or for weeks at a time, it can build up in the bloodstream, causing dizziness, shallow or rapid breathing, and nausea. (Ringing in your ears is usually the first sign of an overdose.) If you're rubbing on the creams for occasional aches, don't worry-just follow the dosage instructions. If the soreness doesn't subside, see your doctor. Never mix muscle ache rubs; stick to one formula at a time.