Liniment, << LIHN uh muhnt, >> is a liquid preparation that is used to treat certain aches and pains in the body. It is usually rubbed on the skin to produce reddening and heat. Liniments usually act by causing irritation or stimulation that increases the blood supply to the area. Liniments often contain stimulating agents such as ammonia and turpentine. Most liniments are poisonous when swallowed. They should not be used on sores and cuts unless a doctor advises it.