The aim of this study was to investigate the relationships between negative mood, the reporting of asthma symptoms, and the use of short-acting bronchodilators (reliever medication). Forty-two adult asthma patients completed a daily questionnaire over 7 consecutive days. The questionnaire measured negative mood and the number of symptoms patients associated with their asthma. The symptoms included those typical of asthma, as well as nonspecific somatic and distress symptoms. Subjects were also asked to record their daily use of reliever medication and their peak flow values. Data analysis demonstrated that even when controlling for lung function, both asthma symptom labeling and negative mood were related to reliever use. A mediation model suggested that negative mood leads patients to associate a wide range of nonspecific symptoms with their asthma, thereby altering the perception of the severity of the asthma, which in turn influences their use of reliever medication. The results of this study are discussed in relation to asthma self-management strategies.