Homeopathy is a system of personalized, natural medicine which stimulates the body's innate ability to heal itself.
It is based on the law of similars. This means that a substance which produces certain symptoms in a healthy person can be used to treat similar systoms in a sick person.
An example is an onion. It causes your eyes and nose to water when you peel it.
Therefore, when a homeopathic remedy is made from the onion family, it can be used to treat an individual with an allergy, who displays similar symptoms, such as watery eyes and a runny nose.
Homeopathic remedies have been diluted beyond substance, but have been energized, and are therefore non-toxic with no side effects.