Amlodipine Research Paper

Amlodipine is a calcium channel blocker that acts on the cardiac muscle and its peripheral vessels. Acting on the myocardial cells, which are responsible for the conduction of the electric stimuli of the heart, Amlodipine causes a decrease of the myocardial contractility [1]. Amlodipine causes dilation of coronary and peripheral arteries which is an important treatment of hypertension, as well as increasing blood flow to the cardiac muscle which aids angina [2].
The Food and Drug Administration (FDA) has already raised concern that the maleate salt of Amlodipine, unlike the besylate and mesylate salts, suffer from intrinsic chemical instability resulting in the formation of a biologically active degradation product [17]. Some studies, including that by Suh et al., report how one of the by-products obtained by the degradation of the maleate salt moiety is a derivate of aspartic acid [18-20]. A citizen’s petition was organised in 2002 to revoke acceptance of Amlodipine maleate as a clinically equivalent option to amlodipine besylate, due to the high biological activity of the impurities obtained from the degradation of the maleate moiety [21]. This was acknowledged by the United States Court of Appeals for the Federal Circuit which temporarily prevented the generic maleate
The majority of medications currently developed and prescribed are in the form of tablets or capsules due to their ease of consumption by the patient. The identification and characterisation of tablets and capsules is a vital process within the drug development timeline, as the pharmaceutical form of a substance can impact significantly its stability and bioavailability [23]. Taylor & Langkildl explain how useful it could be to be able to identify these solid-state medications in situ, particularly where different salts are present [24]. Tablets often contain low doses of API, which can present analytical