Primaxin Online, Description, Chemistry, Ingredients - Imipenem and Cilastatin

Primaxin Online, Description, Chemistry, Ingredients - Imipenem and Cilastatin

To reduce the development of drug-resistant bacteria and maintain the effectiveness of PRIMAXIN I.M.† and other antibacterial drugs, PRIMAXIN I.M. should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.

For Intramuscular Injection Only

PRIMAXIN I.M. (Imipenem and Cilastatin for Injectable Suspension) is a formulation of imipenem (a thienamycin antibiotic) and cilastatin sodium (the inhibitor of the renal dipeptidase, dehydropeptidase I). PRIMAXIN I.M. is a potent broad spectrum antibacterial agent for intramuscular administration.

Imipenem (N-formimidoylthienamycin monohydrate) is a crystalline derivative of thienamycin, which is produced by Streptomyces cattleya. Its chemical name is

[5R-[5a, 6a (R*)]]-6-(1-hydroxyethyl) -3-[[2-[(iminomethyl) amino] ethyl]thio]-7-oxo-1-azabicyclo [3.2.0] hept-2-ene-2-carboxylic acid monohydrate. It is an off-white, nonhygroscopic crystalline compound with a molecular weight of 317.37. It is sparingly soluble in water, and slightly soluble in methanol. Its empirical formula is C₁₂H₁₇N₃O₄S•H₂O,

Cilastatin sodium is the sodium salt of a derivatized heptenoic acid. Its chemical name is [R-[R*,S*-(Z)]]-7-[(2-amino-2-carboxyethyl)thio]-2-[[(2,2-dimethyl yclopropyl)carbonyl]amino]-2-heptenoic acid, monosodium salt. It is an off-white to yellowish-white, hygroscopic, amorphous compound with a molecular weight of 380.43. It is very soluble in water and in methanol. Its empirical formula is C₁₆H₂₅N₂O₅Sna.

PRIMAXIN I.M. 500 contains 32 mg of sodium (1.4 mEq) and PRIMAXIN I.M. 750 contains 48 mg of sodium (2.1 mEq). Prepared PRIMAXIN I.M. suspensions are white to light tan in color. Variations of color within this range do not affect the potency of the product.