A questionnaire survey on the relationship between chewing betel nut and asthma was carried out in 61 asthmatic patients who regularly attend a follow-up clinic at Port Moresby General Hospital. 54 of these had once chewed or were still chewing betel nut; 20 patients had already given it up, while 34 were still regular or occasional chewers. 7 patients had never chewed. 11 of the 20 patients who used to chew but had given up reported having stopped because of aggravation of their asthma. 22 of the 34 patients who still chewed also reported aggravation of their asthma by betel nut. Anecdotal reports were given directly linking specified methods of chewing the nut with asthma aggravation, in some cases indicating dose-response (toxicity) relationships. While more elaborate and objective studies are being undertaken, it is hereby suggested that patients with asthma be cautioned against chewing betel nut.