[A pilot phase II study of combination therapy with oxatomide, an antihistamine, plus dextromethoraphan and bakumondo-to, an herbal drug, in patients with postinfectious persistent cough].

Previously, we reported the effectiveness of treatment with oxatomide (O), an antihistamine, plus dextromethorphan (D), and that of Bakumondo-to (B), an herbal drug that inhibits the activation of C-fibers, in patients with persistent coughing after upper-airway infection. In this study, we evaluated the efficacy and side effects of combination therapy (O + D + B) in patients with postinfectious persistent cough. Patients who had been coughing for more than three weeks and had a history of upper-airway infection took part in the study. None had any history of nasal disease, gastroesophageal reflux, bronchial asthma, or other chronic pulmonary disease. All patients were non-smokers, and none used angiotensin converting enzyme (ACE) inhibitors. All had normal chest roentgenograms and normal pulmonary function. The following hematological data were obtained before treatment: peripheral eosinophil counts. CRP levels, serum IgE concentrations, and titers of cold agglutinins and antibodies to Mycoplasma pneumoniae. The effects of one week of treatment with O + D + B on the severity of coughing, as estimated with a cough diary, were examined. Thirty-six patients entered the study, but only 18 with normal hematological findings who satisfied the study criteria were eligible for efficacy and side-effect analyses. Cough scores decreased significantly from 5.1 +/- 2.4 (range, 2-9) to 1.2 +/- 1.9 (range, 0-6), and the rate of cough disappearance was 50%. Two patients reported slight drowsiness. Therapy with O + D + B reduced perception of coughing as estimated with a cough diary. These results suggest that this therapy (O + D + B) may be useful in patients with postinfectious persistent cough.