Neurological aspects of areca and betel chewing

Betel quid chewing has been claimed to produce a sense of well-being, euphoria, warm sensation of the body, sweating, salivation, palpitation, heightened alertness and increased capacity to work. These effects suggest that betel quid chewing affects predominantly the central and autonomic nervous systems. Several studies have been conducted to elucidate the central and autonomic effects of betel quid chewing. The results are: (1) betel quid chewing increased the heart rate with onset within 2 minutes, maximal effect within 4-6 minutes and an average duration of 16.8 minutes. The cardio-acceleratory response was more prominent for fresh and occasional chewers than for habitual chewers; (2) betel quid chewing increased the skin temperature with onset and duration similar to a cardio-acceleratory response. The hyperthermic effect was abolished by atropine and partly inhibited by propranolol. (3) Betel quid chewing had no effect on simple reaction time but shortened the choice reaction time. (4) Betel quid chewing produced widespread cortical desynchronization of EEG. (5) Chewing of one or two betel quids attenuated the sympathetic skin response while continued consumption of more than two betel quids affected the RR interval variation. (6) Plasma concentrations of noradrenaline and adrenaline were elevated during betel quid chewing. These studies have confirmed several effects claimed by betel quid users. The effects of betel quid chewing appeared to be habit-related and dose-dependent. Although arecoline has been thought to be responsible for several effects of betel quid chewing, the present data suggest a role also played by sympathetic activation.