Sodium pamoate

A hot, filtered solution of 2.27 grams of pyrvinium chloride dihydrate in 250 ml of water is added slowly to a solution of 2.25 grams of sodium pamoate monohydrate in 50 ml of water. A red precipitate immediately forms. The mixture is heated at about 90°-100°C for 5 minutes more and then filtered. The reaction product is washed with hot water and dried at about 75°C in a vacuum. This preparation melts at about 210°-215°C with prior softening from about 190°C. 

Dimethyl sulfoxide 1 -Dimethyl-1,4,5,6-tetrahydro-pyrimidine Pyrantel pamoate 3,5-Dinitrobenzoic acid Diatrizoate sodium Dioctyl sodium sulfosuccinate Docusate calcium... 

Many drug substances are used in the form of a salt. The identification of these materials may also include a test for the specific counterion used. Common counterions used in pharmaceuticals are sodium, chloride, and pamoate ions as illustrated later in Figure 5. 

For sodium or potassium salts of weak acids, the pH of the solution in a diffusion layer is greater than the pH of the diffusion layer for the corresponding weak acid. On the other hand, the pH of the solution in the diffusion layer for hydrochloride salts of weak bases is always smaller than the diffusion layer of the corresponding free base. Therefore, effective solubility and dissolution rate of soluble salts on drug absorption are available in the literature. The potassium salt of penicillin V yields a higher peak plasma concentration of antibiotic than the corresponding free acid (42). Sodium salts of barbiturates are reported by Anderson (43) to provide a rapid onset of sedation. Some salts have a lower solubility and dissolution rate than their parent compounds. Examples include aluminum salts of weak acids and pamoate salts of weak bases. In these particular examples, insoluble films of either weak acids or pamoic acid appear to form in the dissolving solids and further retard the dissolution rate. 

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