OBJECTIVES: It has been reported that 50-65 % of the Indian population has no access to essential medicines, whereas a small portion of the population using medicines, do so irrationally and unnecessarily. Irrational use of medicines leads to wastage of national wealth and also emerging Adverse Drug Reactions (ADRs) and developing resistance to some drugs especially antibiotics. In order to improve the situation, several interventions have been suggested. One such intervention is promoting the concept of Rational Use of Medicines (RUM) through conducting workshops and seminars involving all stake holders in the health care system. This study was conducted to determine the effect of an intervention on drug use pattern in a community METHODS: Study was conducted in the semi urban areas covering three districts of West Bengal, India. Community pharmacies mainly serving the prescriptions of private practioners were involved in this study. Prescriptions were collected from community pharmacies, serving prescriptions of private practitioners in a semi urban area within a month. 30 prescriptions each from 10 pharmacies were collected from the area where workshop/seminars were conducted during the last two years. 30 prescriptions each from 10 pharmacies were collected where no such workshop/seminars were organized for the past two years. RESULTS: Results show that the average number of medicines prescribed per encounter reduced from 2.84 to 2.18. % of prescriptions for generics improved significantly from nil to 22.78. % of prescriptions for antibiotics and vitamin tonics reduced significantly, i.e. from 54.33 to 34.66 and from 16 to 12 respectively, % of prescriptions for injections reduced from 3.66 to 0.33 .Average number of FDCs reduced from 1.13 to 0.55. CONCLUSIONS: It reveals from the result mentioned above that medicine use indicators have improved significantly by intervention i.e. disseminating information on rational use of medicines amongst the stake holders of a health care system.