Cephalexin description
| Cephalexin |
|---|
| CEPHALEXIN®,KEFLEX® FDA Package Insert |
| Description |
| Clinical Pharmacology |
| Microbiology |
| Indications and Usage |
| Contraindications |
| Warnings and Precautions |
| Adverse Reactions |
| Overdosage |
| Dosage and Administration |
| How Supplied |
| Labels and Packages |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1];Associate Editor(s)-in-Chief: Abdurahman Khalil, M.D. [2]
Cephalexin, USP is a semisynthetic cephalosporin antibiotic intended for oral administration. It is 7-(D-α-amino-α-phenylacetamido)-3-methyl-3-cephem-4-carboxylic acid, monohydrate.
Cephalexin has the following structural formula:
The nucleus of cephalexin is related to that of other cephalosporin antibiotics. The compound is a zwitterion; i.e., the molecule contains both a basic and an acidic group. The isoelectric point of cephalexin in water is approximately 4.5 to 5.
The crystalline form of cephalexin which is available is a monohydrate. It is a white crystalline solid having a bitter taste. Solubility in water is low at room temperature; 1 or 2 mg/mL may be dissolved readily, but higher concentrations are obtained with increasing difficulty.
The cephalosporins differ from penicillins in the structure of the bicyclic ring system. Cephalexin has a D-phenylglycyl group as substituent at the 7-amino position and an unsubstituted methyl group at the 3-position.
Each capsule contains cephalexin monohydrate equivalent to 250 mg (720 μmol) or 500 mg (1,439 μmol) of cephalexin.
Inactive Ingredients: CAPSULES: magnesium stearate, silicon dioxide, and sodium starch glycolate.
Capsule Shell and Print Constituents: black iron oxide, D&C Yellow #10 Aluminum Lake, FD&C Blue #1 Aluminum Lake, FD&C Blue #2 Aluminum Lake, FD&C Red #40 Aluminum Lake, gelatin, pharmaceutical glaze modified in SD-45, silicon dioxide or carboxymethylcellulose sodium, sodium lauryl sulfate, titanium dioxide and may contain propylene glycol. In addition, the 250 mg capsule shell contains yellow iron oxide.
After mixing, each 5 mL of cephalexin for oral suspension USP will contain cephalexin monohydrate equivalent to 125 mg (360 μmol) or 250 mg (720 μmol) of cephalexin.
Inactive Ingredients: SUSPENSION: FD&C Red #40, cherry mixed fruit flavor (artificial flavors, benzyl alcohol, maltodextrin, and modified corn starch), silicon dioxide, sodium benzoate, sugar (fruit granulated), and xanthan gum.
Each tablet contains cephalexin monohydrate equivalent to 250 mg (720 μmol) or 500 mg (1,439 μmol) of cephalexin.
Inactive Ingredients: TABLETS: hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, sodium starch glycolate, and titanium dioxide.
References
http://www.accessdata.fda.gov/drugsatfda_docs/label/2006/050405s097lbl.pdf