Botox blocks signals from the nerves to the muscles. The injected muscle can't contract. That makes wrinkles relax and soften. Botox is a drug that temporarily paralyzes muscle. In small doses, it can reduce skin wrinkles and help treat a range of medical conditions, including eyelid spasms, Raynaud's disease, and some types of migraine. Botox is most often used on forehead lines, crow's feet (lines around the eye), and frown lines. Botox won’t help with wrinkles caused by sun damage or gravity. Botox injections also are used to ease symptoms of some health conditions. Botox shots block certain chemical signals from nerves that cause muscles to contract. The most common use of these injections is to relax the facial muscles that cause frown lines and other facial wrinkles.