Allium cepa is the Latin name of the homeopathic remedy made from the red onion. Onions have been used in medicine for hundreds of years, and in various cultures around the world to treat infections and arthritic complaints. Allium was first prepared as a homeopathic remedy by the eminent homeopath, Constantine Hering, M. D., in 1847. The remedy is made from the onion bulb, which was ground and then prepared in alcohol. The tincture was then diluted and succussed (shaken), in accordance with homeopathic methods of pharmacy.

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