Oral solids storage

Candidates with a water uptake (hygroscopicity value) less than 2% w/w after storage at 90% RH for 24 h should present no difficulties for oral solid dose formulation. 

When drugs are to be administered by the parenteral route, solubilization plays a more important role than in oral administration, as with the latter, a solid dosage form is equally acceptable. Therefore the endotoxin-free types, povidone K12 and povidone K 17 are recommended for parenterals. The molecular weight of both products is low enough (see Section 2.2.6) to allow rapid renal elimination without storage. In many countries in Europe, e.g. Germany and Austria, only such low-molecular povidone types with a K-value of up to 18 are approved for injection (see Section 6.1.3). 

Deliquescent, orthorhombic, elongated, six-sided tablets from dimethyl phthalate. dj 1.282. mp 45-46. bp0J 83. Fomin of dicyandiamide begins at 122. Dipole moment in benzene at 2Cryoscopic constant (water) 26.8-28.4. Sp ht 0.547 cal/g/ C between 0° and 39. Heat of formation 14.05 kcal/mole (25 ) heat of combustion —176-4 kcal/-mole (25 ) heat of fusion 2.1 kcal/mole. Heat of vaporization 16.4 kcal/mole. Soly (g/100 g soln) in water at 15 77.5, at 43 100 in butanol at 20 28.8, in methyl ethyl ketone 50.5, in ethyl acetate 42.4. Sol in alcohols, phenols, amines, ethers, ketones. Very sparingly sol in benzene, haJogeaated hydrocarbons. Practically insol in cyclohexane. Solid cyanamide should be stored in a cool, dry place. Polymerizes at 122. Optimum pH for storage of solns is 4, Attacks various metals. Solns can be stored in grass provided they are stabilized with phosphoric, acetic, sulfuric, or boric acid. LDM in rats 125 mg /kg orally. 

All product characteristics likely to be affected by storage, e.g., assay value or potency, content of products of decomposition, physicochemical properties (hardness, disintegration, particulate matter, etc.), should be determined for solid or semi-solid oral dosage forms, dissolution tests should be carried out... 

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