A bitters is a preparation of herbs an citrus dissolved in alcohol or glycerine with a bitter or bittersweet flavor. The various brands of bitters, once numerous, were formerly manufactured as patent medicines, often serving as digestifs. The few remaining varieties are principally used as apéritifs or as flavorings in cocktails. While bitters commonly have an alcoholic strength of up to 45%, they are normally consumed in small amounts, added as a flavoring agent (similar to vanilla flavoring which is also dissolved in alcohol.) In the United Kingdom angostura bitters are not classified as alcoholic beverages due to their bitter taste and can be bought by a person of any age.