Liniment

Liniment (or embrocation), from the Latin linere, to anoint, is a medicated topical preparation for application to the skin. Sometimes called balms or heat rubs, liniments are of a similar or lesser viscosity than lotions and are rubbed in to create friction, unlike lotions, ointments or creams, but patches, sticks and sprays are also available.

Liniments are typically sold to relieve pain and stiffness, such as from sore muscular aches and strains. or arthritis. These are typically formulated from alcohol, acetone, or similar quickly evaporating solvents and contain counterirritant aromatic chemical compounds such as methyl salicilate, benzoin resin, menthol, or capsaicin; they produce a feeling of warmth within the muscle of the area they are applied to, typically acting as rubefacients via a counterirritant effect.

Liniments have been around since antiquity. Opodeldoc is a formulation invented by the Renaissance physician Paracelsus.

The methyl salicylate that is the active analgesic ingredient in some heat-rub products can be toxic if they are used in excess.Heating pads are also not recommended for use with heat rubs, as the added warmth may cause overabsorption of the active ingredients.

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