Due to prevalence of antibiotic resistance, mortality rate due to infectious diseases has been increased up to several times. Newer antibiotics developed will no longer be effective. Hence, there is an urgent need to find alternate antimicrobial therapies with existing antibiotics. This manual provides the information about classification, mechanism of action and general chemical structure of antibiotics, causes and mechanism of antibiotic resistance, antibiotics of natural origin and combination therapies as alternate therapies with herbal extracts or isolated phytoconstituents with another herbal extracts/standard antibiotics; interaction studies of metal ions and bacteriophage with standard antibiotics respectively. It also emphasizes the importance of natural products as alternate source of antibiotics and also obstructions in using the combination therapy efficiently. The present work will be advantageous to researchers, physicians, health care professionals involved in...