A study to monitor adverse drug reactions in patients of chronic obstructive pulmonary disease: focus on theophylline

摘要

Background. Multiple drugs used in the treatment of chronic obstructive pulmonary disease (COPD) may result in a variety of adverse drug reactions (ADR) during therapy. This, in turn, could contribute significantly to morbidity and mortality and thus it is important to monitor such ADRs, with an aim to rationalise drug therapy in these patients. Objective. To monitor adverse drug reactions in patients with COPD in an outpatient setting. Methods. A prospective, hospital based, study was carried out by the Departments of Pharmacology and Respiratory Medicine, Vallabhbhai Patel Chest Institute, Delhi. Out patients diagnosed as COPD were enrolled after taking written informed consent. On the first visit, the general physical examination was done and the prescription was noted and the patient was interrogated for any ADRs. Dechallenge and rechallenge were done wherever feasible and laboratory investigations were performed when desirable. Patients were followed weekly for a month, and evaluated for any new ADRs on each visit. Causality assessment of ADRs was done by the Naranjo?ˉs scale. Results. The drugs prescribed included, inhaled corticosteroids, ??2 agonists and anticholinergics, oral corticosteroids and theophylline, and in some cases N-acetylcysteine. In general, most of the ADRs were non-serious in nature, except for oral N-acetylcysteine induced serious adverse drug reactions which had to be discontinued. Oral theophylline showed a wide profile of adverse effects viz. anxiety and related manifestations, gastrointestinal symptoms, muscle cramps, etc. In most cases causality assessment showed that there was a temporal relationship between the drug administration and occurrence of adverse event. Conclusions. Theophylline needs careful therapeautic dose monitoring and dose individualisation and more safety studies are needed to evaluate all the possible adverse drug reactions and their mechanisms. [Indian J Chest Dis Allied Sci 2008; 50: 199-202]