In a study of 2,061 adults aged 18 and older with a cough lasting less than 29 days and no suspicion of pneumonia, participants were randomly assigned to receive either amoxicillin (1,038 participants) or a placebo (1,023 participants).Neither the duration of symptoms that patients considered "moderately bad", nor the mean symptom duration, differed significantly between the two groups. Two patients in the placebo group and one in the amoxicillin group were admitted to hospital. There was no evidence of selective benefit in the 547 patients aged over 60 years.