OBJECTIVES::  The aim of this study was to evaluate the practice and communication, i.e. the structure, content and interaction between clients and pharmacists in response to patients with adverse drug events in community pharmacies. METHODS::  Observational descriptive simulated client (SC) method was conducted. Thirty community pharmacies in Qatar were randomly selected and randomized into two groups of 15 (Face to Face, n=15 and Telephone Calls, n=15). Two SCs visited all the pharmacies. Pharmacists were presented with a scenario of polycystic ovarian syndrome (PCOS) patient on metformin presenting with bothering diarrhea and requesting the pharmacist assistance. Data collection was through standardized scenario and data collection form which were piloted and refined prior to the study. Primary outcomes included data gathering, labeling, counseling and prescribing practices. RESULTS::  Forty interactions were made with community pharmacists. Majority of pharmacists dispensed medications (90%); antidiarrheal (67.5%) and antibiotics (37.5%). Referral was made by 7 pharmacists (17.5%). Majority of pharmacists did not gather important information from the patient, such as duration of diarrhea and frequency of diarrhea (87.5% and 82.5%, respectively). All pharmacists needed prompting from the SC to discover that this is an ADE from metformin. More than one third of pharmacists did not label any medication dispensed (43.75%). No significant difference was found between groups in data gathering and dispensing (p-value > 0.05). CONCLUSIONS::  Community pharmacy practice in Qatar is inconsistent with current guidelines and best practices with poor data gathering, labeling, counseling and prescribing practices. There is an urgent need for professional development and training programs for community pharmacists.