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By Medifit Education




Cephalexin 2

1.       TYPE OF DRUG- Cephalexin
Cefalexin, also spelled cephalexin, is an antibiotic.


2.       INDICATIONS (USE)- Cephalexin
For the treatment of respiratory tract infections caused by Streptococcus pneumoniae and Streptococcus pyogenes; otitis media due to Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Streptococcus pyogenes, and Moraxella catarrhalis; skin and skin structure infections caused by Staphylococcus aureus and/or Streptococcus pyogenes; bone infections caused by Staphylococcus aureus and/or Proteus mirabilis; genitourinary tract infections, including acute prostatitis, caused by Escherichia coli, Proteus mirabilis, and Klebsiella pneumoniae.


3.       MECHANISM OF ACTION (MOA)- Cephalexin
Cephalexin, like the penicillins, is a beta-lactam antibiotic. By binding to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, it inhibits the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that cephalexin interferes with an autolysin inhibitor.


Oral Route.


5.       ONSET OF EFFECT OR ACTION- Cephalexin
1 hours.


6.        DOSAGE (DOSING INFORMATION)- Cephalexin

Susceptible infections

Adult: 1-2 g daily given in divided doses at 6-, 8-, 12-hours intervals, increased to 6 g in deep-seated infections.

Child: 25-100 mg/kg daily in divided doses. Max: 4 g daily.

CrCl (ml/min)    Dosage Recommendation

40-50               Max: 3 g daily.

10-40               Max: 1.5 g daily.

<10                  Max: 750 mg daily.


Prophylaxis of recurrent urinary tract infections

Adult: 125 mg at night.

CrCl (ml/min)    Dosage Recommendation

40-50               Max: 3 g daily.

10-40               Max: 1.5 g daily.

<10                  Max: 750 mg daily.


7.       HALF LIFE (DURATION OF ACTION)- Cephalexin
1 hour


iarrhea, dizziness, tiredness, headache, stomach upset, abdominal pain, joint pain, vaginal itching or discharge, nausea/vomiting, itching/swelling, and rash. Keflex dosage depends on the condition being treated.


9.       CONTRAINDICATIONS – Cephalexin
Hypersensitivity to cephalosporins


10.   DRUG INTERACTIONS – Cephalexin
Probenecid produces higher and prolonged serum levels.

Potentially Fatal: Increased nephrotoxicity with aminoglycosides and furosemide.


11.   EXCRETION- Cephalexin
Cephalexin is excreted in the urine by glomerular filtration and tubular secretion. Studies showed that over 90% of the drug was excreted unchanged in the urine within 8 hours.



Cephalexin 1

By Medifit Education