145 patients were recruited in the trial while 130 completed it. Patients were randomized to receive zinc sulphate capsules. 220 mgm three times a day or identical placebo. Major outcome variable was 'Sickle cell crisis'. After a follow up of 1.5 years, the mean number of episodes of crisis was 2.46 +/- 1.04 in the intervention group and 5.29 +/- 2.58 in the control group (p < 0.025; 95% CI for difference between groups: 1.98, 3.42). Mean duration of hospital stay was 4.3 +/- 2.2 days in the intervention group and 3.9 +/- 1.6 days in the control group. The difference was not significant (p > 0.05). There was a significant reduction of the mean number of infective episodes and associated morbidity in patients with sickle cell anaemia.