This book is intended to introduce knowledge through case- based learning in the form of actual clinical pharmacology cases with different situations to facilitate for the undergraduate and postgraduate physicians in their early clinical life to choose and rational the choice based on previous knowledge and evidence based. It will contain some sites for calculation of certain parameters in clinical pharmacology fields and also some important algorithms for treatment of certain diseases.I don’t follow the rules for MCQ questions as I use “all of the above “and “more than one answer” in order to introduce as much knowledge as I can to readers. All questions are answered with explanation.