8. Quality, Safety and Efficacy of MedicinesThe safety and effectiveness of pharmaceutical products are two fundamental issues of importance in pharmacotherapy. The safety of a drug is determined by its pharmacological and toxicological profile as well as adverse effects caused by impurities present in the bulk and dosage forms. Impurities contained in medicines often have undesirable pharmacological or toxicological effects which can counterbalance any benefit from their administration (Nageswara et al., 2003). It is therefore quite obvious that products intended for human consumption must be characterized as completely as possible. The quality and safety of a medicine is generally ensured by effective monitoring and control of impurities. Thus, analytical activities regarding the quantification of active ingredients and impurities in drugs are among the most important issues in modern pharmaceutical analysis (Nageswara et al., 2003).9. Regulatory aspectsTo guarantee the quality, clinical performance, effectiveness and safety of a pharmaceutical product, specifications are set and approved by the competent regulatory authorities of each country in which the medicine is marketed. Analytical testing ensures that these specifications are met by confirming the identity, purity and potency of drug substances and drug products before they are marketed. To ensure reliable bioavailability, performance testing of drug products is necessary (Ahuja and Dong, 2005). These performance tests take the form of dissolution or disintegration tests. In the United Kingdom, the MHRA is an executive agency of the Department of Health which sets standards for the safety, quality and performance of medicines for human use. All medicines authorized in the UK are assessed middle of paper......retention time under particular conditions is considered a reasonably unique identifying characteristic of a given compound and can be used to identify the composed using HPLC-MS or HPLC-DAD which are the most powerful techniques in this regard (Ahuja and Dong, 2005). The sensitivity, specificity and accuracy of HPLC-UV for the analysis of TA in drug substances or drug formulations as well as impurities have been validated and applied successfully (Mohammadi et al., 2007). Good resolution for AT and its two known impurities, desfluoro-atorvastatin (DFAT), diastereomer-atorvastatin (DSAT) and other unknown impurities and tablet formulation excipients, can be achieved by adopting a simple HPLC method . The best resolution is obtained using a Luna C18 column with acetonitrile-ammonium acetate buffer and 4-tetrahydrofuran (THF) as mobile phase (Erturk de