cephALEXin

C. diff Risk

Medium

Oral Bioavailability

Excellent

Approximate Cost

$1/day (Liquid $$$$$$)

Spectrum Of Activity

Dosing

Usual dose: 500 mg PO q6h

Post natal age greater than 21 days12.5-25 mg/kg/dose PO QID

Post natal age 8 to 21 days12.5-25 mg/kg/dose PO TID

Post natal age 0 to 7 days12.5-25 mg/kg/dose PO BID

Renally cleared, requires dosage adjustment with changes in renal function. Consult a pharmacist for renal dosing.

General Information

Common Usage

Uncomplicated skin and soft tissue infection, osteomyelitis, MSSA infections

Adverse Effects

  • Allergy/rash (immediate or delayed), cephalexin and amoxicillin have the same side chain, hence cross -allergenicity may occur

  • Can cause positive Coombs, cytopenias, eosinophilia

Oral Liquids

Concentration: 50 mg/mL
Taste: very palatable
Not all strengths of oral liquids are listed nor are available on IWK formulary

For Community Pharmacy:
If cephalexin liquid is not affordable, please dispense tablets.If part tablets are required, please split for patient if required for accurate dosing and counsel family on how to crush tablets or part tablets and to administer with a small amount of juice, jam, apple sauce, crushed bananas or chocolate pudding.

Tablet/Capsule Strengths

500 mg tablet
For Community Pharmacy:
If cephalexin liquid is not affordable, please dispense tablets.If part tablets are required, please split for patient if required for accurate dosing and counsel family on how to crush tablets or part tablets and to administer with a small amount of juice, jam, apple sauce, crushed bananas or chocolate pudding.

Tablets and capsules are preferred especially over an unpleasant tasting liquid.
Not all strengths of oral tablets/capsules are listed and they are not all available on the IWK formulary.

Pharmacology

Antimicrobial class: First generation cephalosporin - oral

Average serum half life:

  • Neonates: 5 hours.

  • Children 3 to 12 months: 2.5 hours.

  • Adults: 0.5-1.2 hours

Route of Elimination: 80% to 100% of dose excreted as unchanged drug in urine within 8 hours