Not the doctor, but I'm someone very familiar with natural remedies, and kanna's effects are not commonly known as yet. It can relax you or make you more nervous, depending on the dosage, and can be habit forming, so it's not recommended for daily use. It's traditional use is as a mild narcotic, though it's not actually a narcotic, but again can be stimulating, like cocaine, though milder. Whereas, 5-HTP is very well researched.