Calcium acetylsalicylate

Metyrapone Acetylsalicylic acid Caraspirin calcium Acetylsalicylic acid chloride Benoryiate Phenprocoumon N-Acetylsulfanilyl chloride Sulfacytine Sulfamethoxazaole 3-Acetylthiomethyl propanoic acid Captopril... 

A number of water-soluble calcium salts provide convenient vehicles for the administration of therapeutic anions. Probably the most widely encountered is the acetylsalicylate of soluble aspirin (patented 1935) the urea complex of calcium acetylsalicylate (water-solubility 231 gdm-3 at 310K, pH 4.8 (717)) is also widely used. Other examples include calcium bromide and bromolactobionate (sedatives), calcium 2-hydroxy-3-mercapto-l-propanesulfonateaurate(III) (chrysanol, antiarthritic), and calcium Af-carbamoylaspartate (tranquillizer). Calcium iron(II) citrate has been used to remedy iron deficiency - it has the advantage of being stable to air oxidation of the iron(II). The cyclamate anion is certainly not therapeutic, but is relevant here. 

Carbasalate calcium is a platelet aggregation inhibitor. It is a mixture of calcium acetylsalicylate and urea. 

Therapeutic Function Analgesic, Antipyretic, Antirheumatic Chemical Name 2-(Acetyloxy)benzoic acid calcium salt Common Name Calcium aspirin Calcium acetylsalicylate Structural Formula ... 

Complex with urea, CltHl8CaN309, carbasalale calcium, acetylsalicylic acid calcium salt complex with urea, calcium acetylsalicylate carbamide, urea calcium acetylsalicylate, carbaspirin calcium, Alcacyl, Calurin, Iromin, Solupsan. Amorphous powder, dec 243-245. Soly in water at 3T 23J mg/ml, pH 4.8. Description and hydrolytic stability Parrott, J. Pharm. Sci. 51, 897 (1962). 

Calcium acetylsalicylate, Ci8Hi403Ca,2H20, Mol. Wt. 434 4, and lithium acetylsalicylate, CgH704Li, Mol. Wt. 186 1, are estimated by weighing their sulphated ash. Caution is necessary when sulphuric acid is added to the ash for sulphating. 1 g CaS04 = 3-191 g calcium aspirin and 1 g Li2S04 --- 3 385 g lithium aspirin. 

Calcium acetylsalicylate may contain small puantities of calcium chloride as a stabiliser, since the salts are more easily hydrolysed than the free acid (Coplans and Green ). 

Protein or calcium deficiency impairs drug metabolism in animals, due to decreased activity of the microsomal enzymes of the liver. The sleeping time by hexobarbitone is increased as a result of prolonged protein malnutrition. Acetylsalicylic acid has been shown to be more toxic to animals on a diet deficient in protein and magnesium. 

Acetylsalicylic acid is usually given by oral administration (0.5-8 g/day) for pain and inflammation and for antiplatelet therapy (75-100 mg/day). It is also available in rectal and topical formulations and as a soluble lysine derivative for intravenous or intramuscular application. Acetylsalicylic acid is often used in multi-drug preparations. The main side-effects are gastrointestinal disorders. Use in children is limited due to the risk of Reye s syndrome (Waldmann et al., 1982). The lithium, magnesium, calcium, and aluminium salts of acetylsalicylic acid are used in some special preparations. 

Acetylsalicylic Acid (ASA) Aspirin Celecoxib Celebrex Diclofenac sodium Voltaren Diflunisal Dolobid Etodolac Iodine Fenoprofen calcium Nalfon... 

Moolenaar F, Oldenhof NJJ, Groenewoud W et al (1979) Biopharmaceutics of rectal administration of drugs in man, part 6, Absorption rate and bioavailability of acetylsalicylic acid and its calcium salt after oral and rectal administration. Pharm Weekbl Sci... 

Generally this will be about the choice of another chemical form, for example theophylline instead of aminophylline or carbasalate calcium instead of acetylsalicylic acid. It is important to pursue a consistent policy on this, for both the stock preparation as well as the extemporaneous preparation and the policy should be clear and consistent. The prescriber should be consulted in order to explain changes to the prescription and in many Countries should be asked consent. 

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