Studying a drug's mechanism of action and evaluating its safety and efficacy from preclinical animal studies, and from veterinary medicine, can indicate potential for use in humans. Through this approach, drugs used in animal care may be repurposed in humans following further testing. For example, miltefosine, a canine antiparasitic agent, was found to be an effective treatment for leishmaniasis, a parasitic infection in humans. The reverse approach is also applicable; gabapentin, developed as an anticonvulsant for humans, has been used to treat chronic pain in animals, and trazodone, used for depression and anxiety in humans, is also prescribed for canine anxiety.