Methods and compositions are provided for the disruption of biofilms and the treatment of disorders characterized by the presence of biofilms and/or abnormally viscous and/or cohesive bodily secretions, such as mucus and sputum. Disorders that can be effectively treated using the disclosed compositions and methods include cystic fibrosis (CF), endocarditis, urinary tract infections, middle-ear infections, chronic sinusitis, gingivitis, periodontal disease, bronchiectasis, chronic obstructive pulmonary disease (COPD), asthma, bronchitis, neonatal meconium aspiration syndrome, smokers' cough, chronic tonsillitis, chronic vaginitis, and fungal or bacterial infections. The compositions, which contain an effective amount of trisodium citrate and ammonium chloride, may be administered alone or in combination with one or more known therapeutic agents.