Chemicals extracted from the skin of "Epipedobates tricolor" may be shown to have medicinal value. Scientists use this poison to make a painkiller. One such chemical is a painkiller 200 times as potent as morphine, called epibatidine; however, the therapeutic dose is very close to the fatal dose. A derivative ABT-594 developed by Abbott Laboratories, called Tebanicline got as far as Phase II trials in humans, but was dropped from further development due to unacceptable incidence of gastrointestinal side effects. Secretions from dendrobatids are also showing promise as muscle relaxants, heart stimulants and appetite suppressants.