Here in Peru you can buy the coca leaf legally in a pulverized form of flour (harina), which can be used to make a tea. Just add a teaspoon of coca flour to a cup of hot water and you have yourself a refreshing cup of tea. The effect is similar to a cup of coffee.
Coca tea can be used in the prevention of altitude sickness, which increases the absorption of oxygen in the blood. The tea originates from the Andes mountain range.