Ceporex A, Keflex, Novolexin A
Classifications: beta-lactam antibiotic; first-generation cephalosporin; Therapeutic: antibiotic; cephalosporin
Pregnancy Category: B
250 mg, 500 mg capsules; 250 mg, 500 mg, 1 g tablets; 125 mg/5 mL, 250 mg/5 mL suspension
Semisynthetic beta-lactam cephalosporin. Preferentially binds to one or more of the penicillin-binding proteins (PBP) located
on cell walls of susceptible organisms. This inhibits third and final stage of bacterial cell wall synthesis, thus killing
Broad-spectrum, first-generation cephalosporin antibiotic active against many gram-positive aerobic cocci and much less
active against gram-negative bacteria or anaerobic organisms.
To treat infections caused by susceptible pathogens in respiratory and urinary tracts, middle ear, skin, soft tissue, and
Hypersensitivity to cephalosporins and related antibiotics; viral infections. Safe use in infants <1 mo not established.
History of hypersensitivity to penicillin or other drug allergy; severely impaired renal function; GI disease, colitis;
hepatic disease; coagulopathy; pregnancy (category B), lactation.
Route & Dosage
|Mild to Moderate Infection
Adult: PO 250500 mg q6h
Child: PO 25100 mg/kg/d in 4 divided doses
Skin and Skin Structure Infections
Adult: PO 500 mg q12h
Child: PO 75100 mg/kg/d in 4 divided doses
- Cephalexin oral suspension should be refrigerated; discard unused portions 14 d after preparation. Label should indicate
expiration date. Keep tightly covered. Shake suspension well before pouring.
Adverse Effects (≥1%) Body as a Whole:
superinfections. GI: Diarrhea
(generally mild), nausea, vomiting, anorexia, abdominal pain. CNS:
Dizziness, headache, fatigue
Diagnostic Test Interference
False-positive urine glucose determinations using copper sulfate reagents (e.g., Clinitest, Benedict's reagent), but not with glucose oxidase (enzymatic) tests (e.g., TesTape, Diastix, Clinistix). Positive direct Coombs' test may complicate transfusion cross-matching procedures and hematologic studies.
decreases renal elimination of cephalexin.
Rapidly from GI tract; stable in stomach acid. Peak:
1 h. Distribution:
Widely distributed in body fluids with highest concentration in kidney; crosses placenta. Elimination:
80100% unchanged in urine in 8 h; excreted in breast milk. Half-Life:
Assessment & Drug Effects
- Determine history of hypersensitivity reactions to cephalosporins and penicillin and history of other drug allergies before
therapy is initiated.
- Lab tests: Evaluate renal and hepatic function periodically in patients receiving prolonged therapy.
- Monitor for manifestations of hypersensitivity (see Signs & Symptoms, Appendix F). Discontinue drug and report their appearance
Patient & Family Education
- Take medication for the full course of therapy as directed by physician.
- Keep physician informed if adverse reactions appear.
- Be alert to S&S of superinfections (see Appendix F). These symptoms should be reported promptly and appropriate therapy