Introduction: Dispensing errors (DE) and health care uncertainty impact on health outcomes in a variety of ways. The aim of initiating therapy is to enhance patient wellness but human error probabilities sometimes cause harm or even fatalities and litigations. Objective: The aims of this study are to discuss the underlying factors in dispensing errors, health care uncertainty and therapeutic outcomes, and to identify the extent of human-and system-based sources of errors by exploring hospital pharmacists' attitudes and dispositions to DE and uncertainties; and the implications for patient safety in a tertiary hospital. Methods: The study involved a sample of 44 pharmacists who were administered a survey research inventory designed to assess pharmacists' attitudes and involvement in DE and uncertainty on a variety of important dimensions. Results: Overall the survey research data showed high rating of five human-based dimensions that would minimize dispensing errors, two human-system based, while three system-based (structural) issues were rated as dimensions that would aggravate DE in uncertain health care scenarios. Conclusions: The practical importance of the results for pharmacy practice and therapeutic outcomes are discussed and some suggestions made on how to minimize DE and uncertainty and the policy implications in the hospital pharmacy setting.