Meditation
Meditation is much more than just relaxation. Numerous studies show that meditation helps in lasting emotional balance.
Every time when we say in our practice, “practice meditation”, just do meditation for 15 minutes or half an hour, it is received with a smile (skeptical). When a medicine, however, would be offered with all the benefits of meditation, the newspapers were written all over.
And all those advantages are within your own range. A simple activity that is totally free, or with guidance against low costs. You only need yourself, no chemicals or books.