OBJECTIVES: To find out the usefulness of Days Lost due to Disability (DLD) in calculating the burden of adverse drug reactions due to diclofenac. METHODS: The study was conducted in 2010 for the cohort dispensed with diclofenac tablets in one pharmacy at South India. Those who were co-prescribed with other anti-inflammatory agents and having serious co-morbidity were excluded from the study. The study subjects (18-65 years) were instructed to report any suspected side effects on their next visit or through phone call. DLD is calculated similar to Years Lost Due to Disability (YLD) by multiplying the occurrence of Adverse Drug Reactions (ADRs), its duration and disability weight. DW was calculated in an analogue scale of 0-1 were 0 is perfect health. Naranjo Causality assessment was used to qualify ADRs on it probability. RESULTS: In a total of 1000 prescription of 943 patients’ 34 types of ADRs were identified with a total score of 561.  The most occurring ADRs were on gastrointestinal system (48%). Abdominal pain occurred for 107 times. There were only 34 cases of peptic ulcers but it was the most disabling ADR with a DLD of 0.078. There were only few cases of acute renal failure (DLD 0.012) and Steven-Johnson Syndrome (DLD 0.013); still they scored a significant DLD as the outcome was more damaging. DLD can be calculated only in recovered patients. DLD is a useful indicator of assessing the burden of ADRs managed in different healthcare settings with varying resources. CONCLUSIONS: DLD could represent the burden of ADR on health. It considers the occurrence, duration and reduction in health due to ADRs. So DLD could be a useful tool in assessing the outcome of ADRs.