Amlodipine Besylate Properties

Name : Amlodipine besylate
Synonyms : Amlodipine besilate; 2-[(2-Aminoethoxy)methyl]-4-(2-chlorophenyl)-3-ethoxycarbonyl-5-methoxycarbonyl-6-methyl-1,4-dihydropyridine benzenesulfonate
Molecular Structure
Molecular Formula : C20H25ClN2O5.C6H6O3S
Molecular Weight : 567.05
Melting point : 199-201 ÂșC
Physical State : white to off-white crystalline powder

Solubility In Water : Slightly soluble
Stability : Stable under ordinary conditions.

Applications and Mechanism Action of Amlodipine Besylate
Calcium ions are needed for electrical activity for the contraction of cardiac and smooth muscle and conduction of nerve cell. Calcium channel blocker is a drug which inhibits the entry of excess calcium into cells and/or prevents form the mobilization of calcium from intracellular stores, resulting in relaxation of blood vessel walls and cardiac muscle for blood to flow more freely, lowering blood pressure thereby reducing oxygen demand in the heart and relieving anginal pain. It is used in the treatment of angina, cardiac arrhythmias, and hypertension.

Some major calcium channel blockers upon chemical structure are:
• Dihydropyridine calcium channel blockers ; Amlodipine, Lacidipine, Lercanidipine, Nicardipine, Nifedipine, Nisoldipine, Nitrendipine, Nimodipine.
• Phenylalkylamine calcium channel blockers ; Gallopamil, Verapamil
• Benzothiazepine calcium channel blockers Diltiazem
• Diarylaminopropylamine ethers: Bepridil, Mibefradil

Amlodipine besylate is used in the treatment of hypertension and chronic stable and vasospastic angina. It a white crystalline powder; slightly soluble in water, propanol; freely soluble in methanol; sparingly soluble in ethanol; melting range 195 - 204 C; administered orally. The chemical designation is (RS) 3-ethyl-5-methyl-2-(2-aminoethoxymethyl)-4-(2-chlorophenyl)- 1,4-dihydro-6-methyl-3,5- pyridinedicarboxylate benzenesulphonate. SALES SPECIFICATION

Amlodipine Besylate Incompatibility
This article studies the compatibility of amlodipine besylate in its solid formulations with various drug excipients. The various factors affecting amlodipine besylate stability were studied using high-performance liquid chromatography (HPLC). It has been found that binary 1:1 mixtures of amlodipine besylate and an excipient are stable at 65 degrees C and 40 degrees C/75% RH. Further investigations were conducted to study the stability of amlodipine besylate in multicomponent mixtures, including mixtures with actual formulations. The study reveals that mixtures of lactose, magnesium stearate, and water induce some instability on amlodipine besylate. The major degradation product confirmed by HPLC-mass spectrometry is amlodipine besylate glycosyl. This is in conformity with the well-known Maillard reaction between primary amines and lactose. Thus, lactose-free amlodipine formulations are recommended from the safety, quality, efficacy, and process cost points of view.

When the Drug substance-Excipient compatibility study of Amlodipine besylate was carried out by Differential Scanning calorimetric technique by using DSC-25 equipped with TC-11 TA Processor (Mettler, Switzerland), Maize Starch, Lactose, Anhydrous Lactose, Directly compressible Lactose, Pregelatinised Starch, Talc, Anhydrous Dicalcium Phosphate, Dicalcium Phosphate engranules, Microcrystalline cellulose and Croscarmellose Sodium are found to be compatible. Lactose, Pregelatinised Starch, Sodium starch Glycolate and Magnesium stearate are found to be incompatible.

When the Drug substance-Excipient compatibility study was carried out by High Performance Liquid Chromatographic analysis of Drug-Excipient mixture samples exposed to accelerated temperature and Humidity conditions over a period of time, it is found that Amlodipine besylate is compatible with Anhydrous Lactose, Directly compressible Lactose, Microcrystalline cellulose, Maize Starch, Anhydrous Dicalcium phosphate, Dicalcium phosphate engranules, Polyvinyl- pyrrolidone, Hydroxy propyl methyl cellulose, Magnesium stearate, Colloidal Silicon dioxide, Talc and Croscarmellose Sodium. Amlodipine besylate was found to be incompatible with Polyvinylpolypyrrolidone, Sodium alginate, Gelatin and Hydroxypropyl Cellulose.