L-carnitine.
Although advertised on the Internet for weight loss, prevention of aging and enhancement of athletic and sexual performance, levocarnitine has only one well-established indication, and that is for treatment of carnitine deficiency. In clinical trials, the drug also seems to have had modest effects in some other conditions, particularly intermittent claudication and recovery after myocardial infarction, but more studies are needed.
D002331:Carnitine / Q000009:adverse effects / Q000172:deficiency* / Q000627:therapeutic use*; D018849:Controlled Clinical Trials as Topic; D003677:Deficiency Diseases / Q000188:drug therapy; D019587:Dietary Supplements / Q000009:adverse effects / Q000706:statistics & numerical data; D004311:Double-Blind Method; D015673:Fatigue Syndrome, Chronic / Q000188:drug therapy; D006801:Humans; D007383:Intermittent Claudication / Q000188:drug therapy; D009325:Nausea / Q000139:chemically induced; D016032:Randomized Controlled Trials as Topic; D014839:Vomiting / Q000139:chemically induced
D002331:Carnitine