_____________________________________________________________________________________________________ *Corresponding author: E-mail: ftmgenc@yahoo.com; Journal of Pharmaceutical Research International 26(1): 1-9, 2019; Article no.JPRI.47537 ISSN: 2456-9119 (Past name: British Journal of Pharmaceutical Research, Past ISSN: 2231-2919, NLM ID: 101631759) Study of Interaction between Tigecycline and Sulbactam Hakan Sezgin Sayiner 1 , Fatma Genç 2* and Fatma Kandemirli 3 1 Department of Infectious Diseases and Medicine, Adiyaman University, Adiyaman, Turkey. 2 Department of General Chemistry, Faculty of Pharmacy, Istanbul Yeni Yuzyil University, Istanbul, Turkey. 3 Department of Biomedical Engineering, Faculty of Engineering and Architecture, Kastamonu University, Kastamonu,Turkey. Authors’ contributions This work was carried out in collaboration among all authors. Author HSS managed the literature searches designed the study, wrote the protocol and interpreted the data. Author FK anchored the field study, gathered the initial data and performed preliminary data analysis. Author FG produced the initial draft. All authors read and approved the final manuscript. Article Information DOI:10.9734/JPRI/2019/v26i130128 Editor(s): (1) Dr. R. Deveswaran, Associate Professor & Head-Drug Design and Development Centre, Faculty of Pharmacy, M.S.Ramaiah University of Applied Sciences, Bangalore. Reviewers: (1) Maria Demetriou, Metaxa Memorial Anticancer Hospital, Greece. (2) Diego Zapelini do Nascimento, University of Southern Santa Catarina, Brazil. (3) Giou-Teng, Yiang, Tzu Chi University, Taiwan. Complete Peer review History: http://www.sdiarticle3.com/review-history/47537 Received 28 December 2018 Accepted 05 March 2019 Published 20 March 2019 ABSTRACT Drug interactions can have desired, reduced or unwanted effects. The probability of interactions increases with the number of drugs taken. Side effects or therapeutic drug interactions can increase or decrease the effects of one or two drugs. Failure may result from clinically meaningful interactions. Clinicians rarely use foreseeable drug-drug interactions to produce the desired therapeutic effect. For example, when we consider two drugs each causing, peripheral neuropathy increases the likelihood of neuropathy occurrence. In this study geometry optimizations of tigecycline and sulbactam drugs and their combination have been carried out with the evaluation of B3LYP/6-311G (d, p), B3LYP/6-311G (2d, 2p) levels, and the reaction mechanism at semi empirical PM6, which was parameterized for biochemical systems and B3LYP/6-311G (d,p) levels. The main objective of the study is to understand the interaction ofsulbactam with tigecycline, to Original Research Article