Synthol is a liquid medical product brand available in France since 1920, though the nature of the product has changed through the brand's history.
1920s
Synthol was developed by Maurice Bunau-Varilla, a prominent newspaper publisher of the early twentieth century, as a tonic. He promoted it as a cure-all tonic.[1]
Chloral hydrate based formula
The brand was acquired by GlaxoSmithKline.[2] Formerly the formula consisted of chloral hydrate, menthol, veratrol, resorcinol and salicylic acid. Sold mainly as a mouthwash in a distinctive black carton, it is also packaged as a gel and spray for the treatment of muscular pain(s).