Cephalexin is a first-generation cephalosporin used for the treatment of respiratory tract infections and dermatological infections caused by staphylococcus.
Drug classes
- Antibiotic
- Cephalosporin (first generation)
- Pregnancy Category B
Therapeutic actions
Bactericidal: Inhibits synthesis of bacterial cell wall, causing cell death.
Indications
- Respiratory tract infections caused by S. pneumoniae, group A beta-hemolytic streptococci
- Dermatologic infections caused by staphylococcus, streptococcus
- Otitis media caused by S. pneumoniae, H. influenzae, streptococcus, staphylococcus, Moraxella catarrhalis
- Bone infections caused by staphylococcus, Proteus mirabilis
- GU infections caused by Escherichia coli, P. mirabilis, Klebsiella
Contraindications
- Contraindicated with allergy to cephalosporins or penicillins.
- Use cautiously with renal failure, lactation, pregnancy.
Available forms
Capsules—250, 500 mg; tablets—250, 500 mg, 1 g; tablets for oral suspension—125, 250 mg; oral suspension—125, 250 mg/5 mL
Dosages
ADULTS
1–4 g/day in divided doses; 250 mg PO q 6 hr usual dose.
- Skin and skin-structure infections: 500 mg PO q 12 hr. Larger doses may be needed in severe cases; do not exceed 4 g/day.
PEDIATRIC PATIENTS
25–50 mg/kg/day PO in divided doses.
- Skin and skin-structure infections: Divide total daily dose, and give q 12 hr. Dosage may be doubled in severe cases.
- Otitis media: 75–100 mg/kg/day PO in four divided doses.
Adverse effects
- CNS: Headache, dizziness, lethargy, paresthesias
- GI: Nausea, vomiting,diarrhea, anorexia, abdominal pain, flatulence, pseudomembranous colitis, liver toxicity
- GU: Nephrotoxicity
- Hematologic: Bone marrowdepression
- Hypersensitivity:Ranging from rash to fever to anaphylaxis; serum sickness reaction
- Other: Superinfections
Nursing Interventions
- Arrange for culture and sensitivity tests of infection before and during therapy if infection does not resolve.
- Give drug with meals; arrange for small, frequent meals if GI complications occur.
- Refrigerate suspension, discard after 14 days.
Patient Education
- Take this drug with food. Refrigerate suspension; discard any drug after 14 days.
- Complete the full course of this drug even if you feel better.
- This drug is prescribed for this particular infection; do not self-treat any other infection.
- You may experience these side effects: Stomach upset, loss of appetite, nausea (take drug with food); diarrhea; headache, dizziness.
- Report severe diarrhea with blood, pus, or mucus; rash or hives; difficulty breathing; unusual tiredness, fatigue; unusual bleeding or bruising.
