Rock candy has been used as a medicine for sore throats and colds. The popular candy could be mixed with hot tea or alcoholic cocktails. Adding rock candy to alcoholic beverages became popular in the US to get around temperance laws, the regulated availability of alcohol in order to control consumption, by claiming the beverage was prepared for medicinal purposes. Rock candy is also used in traditional Chinese medicine. It's thought to strengthen the spleen and relieve coughs.
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