Betel quid: Its tremor-producing effects in residents of Araihazar, Bangladesh.

Betel quid consists of a betel nut (Areca catechu) and other additives. It is chewed throughout Asia and is the fourth most commonly used addictive substance in the world. Its stimulant properties are mediated by arecoline and other toxins. The neurological effects of betel quid use have not been studied extensively. To assess tremor, 100 residents of Araihazar, Bangladesh, were asked to draw spirals, which were rated by a blinded neurologist. The average tremor rating was 50% higher in exposed versus unexposed individuals. Betel quid use can produce clinically evident tremor. Population-based epidemiological studies of tremor in Asia should begin to take the effect of this stimulant into account.