The source of this remedy is Peruvian bark, which was taken from South America to Europe by Jesuits in the 17th century. This bark is of particular historical significance for homeopaths, since quinine extracted from it became the subject of Hahnemann's first homeopathic proving. In 1790 he tested quinine on himself, and noticed that it caused symptoms similar to the malaria for which it was prescribed as a cure. He developed the remedy China, which has become a key treatment for malarial symptoms and exhaustion due to fluid loss or long-term illness. China is thought to work best for idealistic, artistic people. Despite problems articulating their feelings, they prefer meaningful talk to trivial chat, but their own intensity often tires them, causing irritability, laziness, depression, violence, or intolerance. Easily offended, they may feel paranoid and mistreated, or that they have been born unfortunate, as if the world is hostile to them. A highly active imagination can lead to a preoccupation with future plans and to egocentric, heroic fantasies that later cause embarrassment. Physical symptoms may be linked to weaknesses in the liver and digestive system and generally include a dislike of butter and other fatty foods, and cravings for alcohol and foods that are sweet or spicy. The remedy is used for exhaustion following illness or extreme fluid loss. China is also given for fever, insomnia, gastric upsets, and headaches. China is used mainly for nervous exhaustion that results from a debilitating illness, weakness from breastfeeding, or an extreme loss of bodily fluids, for example, from sweating, vomiting, or diarrhea. This remedy is also good for the following: headaches that are better from applying firm pressure to the painful area but are worse with light touch, such as combing the hair; neuralgia; convulsions; dizziness; tinnitus (ringing in the ears); twitchy muscles associated with fatigue; and hemorrhages and nosebleeds. China is also given for profuse sweating, shivering, and flushing with or without fever. During sweats the person refuses to drink, but during chills wants to. The complexion appears yellowish and sallow, and the skin is very sensitive to the slightest touch. China is helpful for mental symptoms including lack of concentration, apathy and indifference, edginess, and uncharacteristic, angry outbursts. Sleep may be restless and difficult. People who need this remedy may have swollen ankles, indigestion that is not relieved by burping, and a sensation of food being stuck behind the breastbone. Exhaustion - extreme lethargy, with weak, jumpy muscles, and oversensitivity to noises, smells, and touch. Fatigue can be due to extensive fluid loss caused by diarrhea, severe vomiting, or possibly breast-feeding. It can also be a result of anemia, possibly linked to blood loss or heavy menstrual flow, or to debilitating illness, such as chronic fatigue syndrome (CFS). Insomnia - sleeplessness due to excited thoughts and heroic fantasies. Even the slightest noise disrupts sleep. The mind tends to be very clear in the evening and at night. Digestive disorders - the abdomen may feel bloated. Gas that is difficult to expel may cause pain or, alternatively, pain may remain even after expulsion of gas. There may be attacks of profuse, watery, painless diarrhea. The appetite may be disturbed, causing either great hunger at night or a complete loss of appetite which, however, returns after the first mouthful of a meal. A bitter taste in the mouth may arise from an unsettled stomach. In addition, China may be prescribed to treat digestive symptoms arising as a result of gastroenteritis and disorders of the gallbladder.