Every day various Pharmaceutical products being marketed by various Pharmaceutical companies and various problems arises after the product gets approved and marketed.As coprescription of various drugs is a common practice of health care practitioners in our country resulting in significant drug-drug interactions in local population and are very much challenging because one drug may alter bioavailability of any of the other drug at its receptor site. Mostly they resulted due to any significant change in ADME(absorption,distribution,metabolism and elimination).These interactions lead to serious adverse effects and sometimes lead to death.Some other factors like self-medication,lack of professional pharmacist at pharmacy, racial and ethnic differences contribute to development of ADRs(Adverse drug reactions).It also increase professional liability of Pharmacist that by knowledge of pharmacokinetic tools they point out various drug-drug interactions and provide appropriate guide line for better pharmacotherapy. Drug-drug interaction study can be analyzed by various pre-clinical and clinical experimental ways.The present study mainly focused on compartmental and non-compartmental method of analysis.In this method pharmacokinetic drug-drug interaction analyze followed by statistical comparision of some parameters.It is relatively a simple and rapid method.If most of pharmacokinetic parameters analyzed showed a significant statistical difference demonstrate the manifestation of drug-drug interaction. During the present study pharmacokinetic interaction between oral combination of amino penicillin and a beta-lactamase inhibitor i.e. Co-amoxiclav(250 mg amoxicillin + 125 mg clavulanic acid) with an antacid(10 ml) containing aluminium hydroxide,magnesium hydroxide and simethicone were evaluated.As it is most common practice of using this combination in local population not only prescribed but also as self medication.The data obtained was used to compare pharmacokinetic parameters of Co-amoxiclave alone and with simultaneous administration of antacid.Initially Physico-chemical test were performed for augmentin to check the quality of product.