There are several theories on the cause of ACE inhibitor-induced cough, but the exact mechanism is not known. In many patients, if cough develops, the ACE inhibitor can be discontinued and a drug in another therapeutic class used in its place. However, in patients with CHF, diabetic nephropathy, and patients who have experienced a myocardial infarction, discontinuing the ACE inhibitor may not be in the best interest of the patient. In this patient population it would be reasonable to try cromolyn sodium to treat cough, while continuing the ACE inhibitor. Data are not available to support the efficacy of cromolyn sodium to treat cough in patients with diabetic nephropathy, but these patients clearly benefit from the use of an ACE inhibitor. Other factors not addressed in the case reports and the clinical trial such as patient adherence, cost, and quality of life should also play a role in the decision to use cromolyn sodium. Cromolyn sodium has been effective for the treatment of ACE inhibitor-induced cough in many case reports and has had mild success in one small clinical trial. Although none of the reports adequately assessed adverse effects, studies examining cromolyn for other indications have demonstrated a relatively benign adverse effect profile. It is difficult to recommend an exact dose to use because of the dosing variability in the case reports. The majority of the case reports and the one clinical trial used dosages similar to recommendations for bronchial asthma (i.e., 2 puffs [1.6 mg] 4 times daily via MDI or 20-mg capsules 4 times daily via breath-activated inhalation). At this time, the use of cromolyn sodium is a viable option, but more controlled studies are needed to fully elucidate its role in the treatment of ACE inhibitor-induced cough.