Duricef (Cefadroxil)

Cefadroxil (Duricef): Overview

Cefadroxil is an oral, first-generation cephalosporin (a beta-lactam antibiotic) used for the treatment of mild to moderate infections caused by susceptible bacteria. It is closely related to cefalexin but typically produces more sustained plasma concentrations after dosing.

Duricef: What it is used for

Duricef for strep throat

Duricef (cefadroxil) may be prescribed for streptococcal pharyngitis/tonsillitis (strep throat) when the infection is confirmed or strongly suspected to be bacterial. Because many sore throats are viral, clinicians often rely on rapid testing or culture before selecting an antibiotic. For strep throat, completing the full prescribed course is important to reduce complications and recurrence.

Duricef for skin infection

Duricef is commonly used for uncomplicated skin and soft tissue infections caused by susceptible staphylococci and streptococci (for example, mild cellulitis, infected dermatitis, or other superficial bacterial skin infections). If there is abscess formation, drainage and local management may be required in addition to antibiotics.

Duricef for sinus infection

Sinus symptoms are frequently caused by viruses and may not require antibiotics. Duricef is not a universal first-choice for sinus infections, but it may be used in selected cases of bacterial sinusitis when the suspected or confirmed bacteria are susceptible and a clinician considers it appropriate. Seek medical advice if symptoms are severe, last more than 10 days without improvement, or worsen after initial improvement.

Duricef for tooth infection

Dental (odontogenic) infections are often polymicrobial and commonly require source control (e.g., dental drainage, root canal treatment, or extraction) alongside any antibiotic. Cefadroxil has been used in some orofacial/odontogenic infections, but antibiotic choice depends on severity, suspected bacteria (including anaerobes), and patient allergy history. Urgent dental or emergency assessment is needed if there is facial swelling, fever, spreading redness, difficulty swallowing, or breathing problems.

Cefadroxil: Uses and Administration

Duricef 250mg, 500mg Tablets

Cefadroxil is a first-generation cephalosporin antibacterial that is the parahydroxy derivative of cefalexin, and is used similarly in the treatment of mild to moderate susceptible infections. It is given orally, and doses are expressed in terms of the anhydrous substance; 1.04 g of cefadroxil monohydrate is equivalent to about 1 g of anhydrous cefadroxil. The usual adult dose is 1 to 2 g daily as a single dose or in two divided doses. The following doses are used in children weighing less than 40 kg: 500 mg twice daily for those over 6 years of age, 250 mg twice daily for those aged 1 to 6 years, and 25 mg/kg daily in divided doses for infants under 1 year. For details of reduced doses of cefadroxil [Duricef 250mg, 500mg Tablets] in patients with renal impairment, see below. Cefadroxil [Duricef 250mg, 500mg Tablets] has also been used as the lysine derivative.

Administration in renal impairment

Following an initial loading dose of 0.5 to 1 g, dosage of cefadroxil should be adjusted in patients with renal impairment according to creatinine clearance (CC):

• CC 26 to 50 mL/minute per 1.73 m²: 0.5 to 1 g every 12 hours
• CC 11 to 25 mL/minute per 1.73 m²: 0.5 to 1 g every 24 hours
• CC 10 mL/minute per 1.73 m² or less: 0.5 to 1 g every 36 hours

Adverse Effects and Precautions

Common adverse effects

Cefadroxil is generally well tolerated. The most frequently reported adverse effects involve the gastrointestinal tract (e.g., nausea, vomiting, abdominal discomfort, and diarrhoea) and hypersensitivity reactions (e.g., rash, pruritus, urticaria). As with other antibiotics, cefadroxil may rarely cause antibiotic-associated colitis, including C. difficile-associated diarrhoea.

Precautions

Use cefadroxil with caution in patients with a history of hypersensitivity to cephalosporins. Cross-reactivity may occur in patients with penicillin allergy. Dose adjustment is required in renal impairment (see above), and patients receiving prolonged therapy should be monitored clinically.

Breast feeding

Although higher concentrations of cefadroxil were reported in breast milk compared with cefalexin, cefalotin, cefapirin, and cefotaxime, no detectable cefadroxil would be expected in breast-fed infants and no adverse effects have been seen in infants whose mothers were receiving cefadroxil. Accordingly, the American Academy of Pediatrics considers that cefadroxil is usually compatible with breast feeding.

Cefadroxil: Interactions

Probenecid may increase and prolong cefadroxil plasma concentrations by reducing renal tubular secretion. Anticoagulants (e.g., warfarin) may have enhanced effects when used with some antibiotics; consider clinical monitoring (e.g., INR) when cefadroxil is started or stopped in patients on anticoagulation. As with other antibacterials, cefadroxil may reduce the effectiveness of live bacterial vaccines (where applicable) if administered concurrently.

Duricef and Alcohol

There is no well-known “disulfiram-like” reaction with cefadroxil. However, alcohol can worsen side effects such as stomach upset or dizziness and may slow recovery if intake is heavy. A cautious approach is to avoid or limit alcohol while you are unwell and taking antibiotics, and follow your prescriber’s advice.

Storage

• Tablets/capsules: Store at room temperature in a tightly closed container, away from heat, moisture, and direct light. Do not freeze.
• Oral suspension (liquid): Store in the refrigerator. Do not freeze. Discard any unused portion after 14 days (or as directed on the label).

Antimicrobial Action

Cefadroxil is a bactericidal beta-lactam antibiotic that inhibits bacterial cell-wall synthesis by binding to penicillin-binding proteins (PBPs), disrupting peptidoglycan cross-linking and leading to cell lysis. Its activity is typical of first-generation cephalosporins: good activity against susceptible Gram-positive organisms (including streptococci and methicillin-susceptible staphylococci) and limited Gram-negative coverage (commonly including E. coli, Proteus mirabilis, and Klebsiella spp.). Cefadroxil is not reliably active against MRSA, enterococci, or Pseudomonas spp.

Pharmacokinetics

Cefadroxil is almost completely absorbed from the gastrointestinal tract. After oral doses of 500 mg and 1 g, peak plasma concentrations of about 16 and 30 micrograms/mL respectively are obtained after 1.5 to 2 hours. Although peak concentrations are similar to those of cefalexin, plasma concentrations are more sustained. Dosage with food does not appear to affect the absorption of cefadroxil. About 20% of cefadroxil is reported to be bound to plasma proteins. The plasma half-life of cefadroxil is about 1.5 hours and is prolonged in patients with renal impairment. Cefadroxil [Duricef 250mg, 500mg Tablets] is widely distributed to body tissues and fluids. It crosses the placenta and appears in breast milk. More than 90% of a dose of cefadroxil may be excreted unchanged in the urine within 24 hours by glomerular filtration and tubular secretion; peak urinary concentrations of 1.8 mg/mL have been reported after a dose of 500 mg. Cefadroxil is removed by haemodialysis.

Cefadroxil (Duricef) is a convenient oral first-generation cephalosporin commonly used for susceptible skin infections and streptococcal throat infections, and it may be considered in selected cases of other bacterial infections when appropriate. For best results, take it exactly as prescribed and complete the full course. Patients with beta-lactam allergy, renal impairment, or those using anticoagulants should seek medical advice and appropriate monitoring where needed.