Introduction
Long-acting, broad-spectrum, water-soluble, cephalexin derivative.
Uses
Cefadroxil is a cephalosporin antibiotic used in the treatment of various bacterial infections, such as urinary tract infections, skin and skin structure infections, and tonsillitis.
For the treatment of the following infections (skin, UTI, ENT) caused by; S. pneumoniae, H. influenzae, staphylococci, S. pyogenes (group A beta-hemolytic streptococci), E. coli, P. mirabilis, Klebsiella sp, coagulase-negative staphylococci and Streptococcus pyogenes
Associated Conditions
Pharmacodynamics
Cefadroxil, a first-generation cephalosporin antibiotic, is used to treat urinary tract infections, skin and skin structure infections, pharyngitis, and tonsillitis.
Mechanism of Action
Like all beta-lactam antibiotics, cefadroxil binds to specific penicillin-binding proteins (PBPs) located inside the bacterial cell wall, causing the inhibition of 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 cefadroxil interferes with an autolysin inhibitor.
Absorption
Cefadroxil is well absorbed on oral administration; food does not interfere with its absorption.
Protein Binding
Binding rates of cefadroxil were 28.1% by U.F. method
Route of Elimination
Over 90% of the drug is excreted unchanged in the urine within 24 hours. Cefadroxil was detected in the placenta and breast milk.
Half Life
1.5 hours
Toxicity
Nausea, vomiting, diarrhoea, allergic rashes may occur
Food Interactions
- Take with or without food. Administration with food may be helpful in diminishing potential gastrointestinal complaints occasionally associated with oral cephalosporin therapy.
Dosage
Streptococcal pharyngitis and tonsillitis-
- Adult and adolescents >40 kg with normal renal function: 1000 mg once a day over at least 10 days. Dosage may be decreased.
- Children <40 kg with normal renal function: 30 mg/kg/day once a day over at least 10 days.
- Adult and adolescents >40 kg with normal renal function: 1000 mg twice a day.
- Children <40 kg with normal renal function: 30-35 mg/kg/day divided into two daily doses.
Renal impairment patients: In patients with renal impairment, the dose should be adjusted according to creatinine clearance rates to prevent accumulation of cefadroxil. In patients with creatinine clearance of 50 ml/min or less, the following reduced dosage schedule is recommended as a guideline.
- Creatinine clearance 50-25 ml/min/1.73 m2: 500 mg-1000 mg every 12 hours
- Creatinine clearance 25-10 ml/min/1.73 m2: 500 mg-1000 mg every 24 hours
- Creatinine clearance 10-0 ml/min/1.73 m2: 500 mg-1000 mg every 36 hours
- Children (<40 kg) with renal impairment: Cefadroxil is not indicated in children suffering from renal insufficiency and children requiring haemodialysis.
- Dosage for haemodialysis patients: Haemodialysis eliminates 63% of 1000 mg of cephalosporin after 6 to 8 hours of haemodialysis. Elimination half-time of cephalosporin is about 3 hours during dialysis. Patients with haemodialysis receive one additional dose ofcefadroxil 500 mg-1000 mg at the end of the haemodialysis.
- Elderly: As cefadroxil is excreted by renal route, the dosage should be adjusted if necessary as described under impaired renal function.
Duration of therapy: Treatment should be applied for 2 to 3 further days after regression of the acute clinical symptoms or evidence of bacterial eradication has been obtained. In infections caused by Streptococcus pyogenes up to 10 days treatment may be considered.
