Popularly known as Spanish fly, cantharis is actually a beetle found in southern France and Spain. It produces an irritant so caustic that the skin will blister if exposed to it. Cantharis has had a long career in medicine and has been used for all manner of disorders. In high concentrations the irritant can be toxic, prompting abdominal cramps and burning pains in the throat and stomach, vomiting of blood, diarrhea, kidney damage, convulsions, coma, and death. Homeopaths prescribe Cantharis for patients whose ailments are coupled with symptoms like those of cantharis poisoning. According to homeopathic tradition, the beetles are collected at daybreak, when they are still sluggish from the cool of the night, and heated in the steam of boiling vinegar until dead. The beetles are then crushed and mixed with successively greater amounts of milk sugar, a pharmaceutical process called trituration. The resulting powder is highly dilute. Cantharis is mainly used to treat severe cystitis with a burning, scalding pain that gets worse as urine is passed. It is also given for other urinary tract infections and for scalds and burns that are helped by cold compresses. This remedy is also effective for irritation of the digestive tract that leads to a distended abdomen; !burning pain and scalding diarrhea; a burning sensation on the soles of the feet at night; icy hands with red, hot fingernails; pus filled rashes on the hands; and black-centered stings. Other physical symptoms eased by this remedy include loss of appetite, burning sensations in the throat, and a great thirst but no desire to drink. Mental problems alleviated by Cantharis include an excessive desire for sexual intercourse, fits of rage, irritability leading to violence, severe anxiety, screaming, and insolence.