Spectrum: Local Antimicrobial Stewardship, for Markham Stouffville Hospital

Cephalexin

C. diff Risk

Medium

Oral Bioavailability

Moderate

Approximate Cost

Spectrum Of Activity

General Spectrum of Activity

Spectrum Of Activity

General Spectrum of Activity

Antibiogram Data

Dosing

Renal

CrCl Less Than 10 mL/minGive 50% of dose BID

CrCl 10-24 mL/minReduce dosing frequency to BID

CrCl 25-49 mL/minReduce dosing frequency to TID

CrCl Greater Than 50 mL/minGive usual dose

Adult

250-1000mg PO QID

General Information

Common Usage

Common Usage

  •  Uncomplicated skin and soft tissue infection

  •  MSSA infections

  • Uncomplicated Cystitis

Adverse Effects

Adverse Effects

  •  Allergy/rash (immediate or delayed)

  • Dermatologic reactions including erythema multiforme, Stevens-Johnson Syndrome (rare) and Toxic Epidermal Necrolysis (rare)

  •  Positive Coombs

  •  Cytopenias

  •  Eosinophilia

  • CNS effects including agitation, hallucination, confusion, fatigue, headache, dizziness

  •  Hepatic & renal laboratory abnormalities

  • GI disturbances (diarrhea, nausea)

  • Arthralgia, arthropathy

  • Interstitial Nephritis (rare)

Major Interactions

Major Interactions

Increases metformin levels

May enhance anticoagulant effect of vitamin K antagonists (including warfarin)

May decrease the levels/effects of: BCG (intravesical or vaccine); Cholera vaccine; Typhoid vaccine; Estriol, Sodium Picosulfate, Lactobacillus.

Some vitamins and minerals may reduce absorption/levels of cephalexin

Pharmacology

Pharmacology

Antimicrobial class: First Generation Cephalosporin.

Pregnancy category: B

Average serum half life: 0.5-1.2 hr (longer with renal impairment)

Biliary penetration: Moderate

CSF penetration: Poor

Lung penetration: Moderate

Urine penetration: Therapeutic