BACKGROUND AND OBJECTIVE: Thai community pharmacists are allowed to dispense antibiotics without prescription, and are frequently faced with problems of upper respiratory infections (URI). This study used the theory of planned behaviour to investigate predictors of intention to dispense antibiotics for URI among community pharmacists. METHODS: Self-administered questionnaires were mailed to all community pharmacists in the south of Thailand, measuring intention to dispense antibiotics, attitude, subjective norm, perceived behavioural control, behavioural beliefs, normative beliefs and control beliefs. RESULTS AND DISCUSSION: A total of 656 completed questionnaires were returned out of 833 sent. The pharmacists' intention to dispense antibiotics for URI was low (mean +/- SD; 2.35 +/- 1.85 on a 7-point scale), and strongly influenced by attitude. The beliefs in no benefit of antibiotics had the strongest effects on attitude. Subjective norm had a weak effect on intention, whereas perceived behavioural control had practically no effect. CONCLUSION: Based on this experience of well-informed community pharmacists having proper intention of practice and low control effect, future programme for rational drug use should emphasize education rather than regulation.