This book is also useful for other competitive examinations conducted by Civil Services like IAS, IPS, IFS examinations also. It is the first attempt to provide an information regarding clinical aspects for Medical, Dental, Pharmacy and Veterinary students and we shall appeal to our learned friends and colleagues to favor us with their comments and valuable suggestions for the further improvement of this book. All authors of this book make it easier to recognize the relevance of Physiological, pharmacological and Toxicological facts for little guidance at a glance.It was a great pleasure to edit this book with the help of authors of this book also. We would like to acknowledge the suggestions of few Physiologists who helped in making this book. Some of my Physiology colleagues offered invaluable suggestions in preparing this book. Few Physiologists who helped this book progress, we express our sincere gratitude and appreciation for a job well done.