Khat is an integral part of the cultural in many countries around the Arabian peninsula and Africa, being particularly prevalent in Ethiopia, Somalia, Madagascar and the Yemen. Only the leaves of the plant are chewed and they perish quickly so khat has to be flown out quickly to users abroad before it grows stale or rots.
Whilst mainly a drug enjoyed by men in Africa, in the Yemen 35% of women are reported to be lifelong users, though 60% of the men enjoy chewing khat and the quality is sometimes measured by the number of soap bars one gets through when masturbating on khat, a relaxant so powerful that it becomes difficult to ejaculate. Wait until the drug companies read this and they’ll be selling Khatzac, a premature ejaculation pill to accompany Viagra.
The Koran doesn’t say anything about khat because like marijuana, there wasn’t enough around in the times of Muhammad for him to have any pious moments on the subject. Still, some Muslims hold that anything bad for the body is un-Islamic. Doesn’t seem to stop them eating white sugar, using chemicals in the production of food or using cheap, saturated oils, though.