Natural menthol is obtained by freezing peppermint oil. Used as an antipruritic to reduce itching, As a topical analgesic, it is used to relieve minor aches and pains, such as muscle cramps, sprains, headaches and similar conditions, As a penetration enhancer in transdermal drug delivery. In decongestants for chest and sinuses, In aftershave products to relieve razor burn, As a smoking tobacco additive in some cigarette brands, for flavor, and to reduce throat and sinus irritation caused by smoking. Menthol also increases nicotine receptor density, commonly used in oral hygiene products and bad-breath remedies, such as mouthwash, toothpaste, mouth and tongue sprays, and more generally as a food flavor agent. In perfumery, menthol is used to prepare menthyl esters to emphasize floral notes.