Cefaclor in Wound Care: When and How It's Used

When a wound gets infected, choosing the right antibiotic isn’t just about what works-it’s about what works without causing more problems. Cefaclor, a second-generation cephalosporin, shows up in wound care more often than many realize, especially in outpatient settings. But it’s not a go-to for every infected cut or scrape. Knowing when it fits-and when it doesn’t-can mean the difference between healing and complications.

What Cefaclor Actually Does

Cefaclor fights bacteria by breaking down their cell walls. It’s effective against common skin and soft tissue pathogens like Staphylococcus aureus (including some penicillin-resistant strains) and Streptococcus pyogenes. It also covers some gram-negative bacteria like Escherichia coli and Klebsiella pneumoniae, though not as strongly as later-generation antibiotics.

It’s taken orally, which makes it convenient. No IVs, no clinic visits. That’s why doctors sometimes prescribe it for mild to moderate cellulitis, abscesses after drainage, or infected insect bites when the patient can’t get to a clinic regularly.

But here’s the catch: cefaclor doesn’t work against MRSA. If your wound is oozing thick, yellow pus and isn’t improving after a couple days of cefaclor, MRSA might be the culprit. That’s when you need clindamycin, trimethoprim-sulfamethoxazole, or doxycycline instead.

When Cefaclor Works Best in Wound Care

Cefaclor shines in three real-world scenarios:

1. Minor cellulitis - Red, warm, swollen skin spreading slowly from a small cut, scratch, or insect bite. If the patient is otherwise healthy and the infection isn’t deep, cefaclor is often the first oral choice.
2. Post-drainage abscesses - After a doctor drains a pocket of pus, they may prescribe cefaclor to prevent recurrence, especially if the wound is clean and the patient has no fever or signs of systemic infection.
3. Diabetic foot ulcers with mild infection - In early stages, when infection is limited to the skin and superficial tissue, cefaclor can be part of a treatment plan. But if bone involvement or deep tissue infection is suspected, stronger drugs like amoxicillin-clavulanate or clindamycin are preferred.

A 2023 study in the Journal of Clinical Infectious Diseases tracked 412 patients with uncomplicated skin infections treated with oral antibiotics. Those on cefaclor had a 92% clinical success rate when the infection was caused by susceptible strains. But success dropped to 41% when MRSA was present.

When Cefaclor Falls Short

Not every infected wound needs cefaclor-and some shouldn’t get it at all.

• Deep or large abscesses - Antibiotics alone won’t fix these. Drainage is essential. Cefaclor might help after, but not before.
• Diabetic foot ulcers with osteomyelitis - Bone infections require longer courses of antibiotics that penetrate bone tissue better, like clindamycin or linezolid.
• Animal bites - Dog and cat bites often involve Pasteurella multocida, which cefaclor handles poorly. Amoxicillin-clavulanate is the gold standard here.
• Wounds with greenish discharge - That’s often Pseudomonas aeruginosa, which cefaclor can’t touch. You’d need ciprofloxacin or a different class of antibiotic.

Also, cefaclor isn’t first-line for burns. Burn wounds are prone to multidrug-resistant organisms, and broader coverage is needed from the start.

Dosing and Duration

For adults, the typical dose is 250 mg every 8 hours. Some providers use 500 mg every 12 hours for convenience, but studies show the 8-hour schedule maintains better blood levels.

Duration? Usually 7 to 10 days. Don’t stop early just because the redness fades. Stopping too soon is one of the biggest reasons infections come back-or worse, become resistant.

For kids, dosing is weight-based: 20 mg/kg/day divided into three doses. Never give cefaclor to infants under 3 months unless under direct pediatric infectious disease supervision. Their kidneys aren’t mature enough to clear it safely.

Side Effects and Risks

Cefaclor is generally well-tolerated, but it’s not harmless.

• Diarrhea - Up to 10% of users get it. If it’s watery and frequent, especially with cramps or fever, it could be C. diff. Stop the drug and get tested.
• Allergic reactions - Rash, itching, swelling. If you’re allergic to penicillin, you have a 5-10% chance of reacting to cefaclor too. Not a guarantee, but a risk.
• Nausea and vomiting - Usually mild. Taking it with food helps.
• False positive urine glucose tests - If you’re diabetic and testing urine for sugar, cefaclor can trick the strips. Use blood glucose meters instead.

People with kidney disease need lower doses. Cefaclor is cleared by the kidneys. If your eGFR is below 30 mL/min, the dose should be cut in half and given every 12 hours.

Alternatives to Cefaclor

If cefaclor isn’t right for your wound, here are common alternatives:

Comparison of Common Oral Antibiotics for Wound Infections

Antibiotic	Best For	Limitations	Typical Dose
Cefaclor	Mild cellulitis, post-drainage care	Not for MRSA, Pseudomonas, or deep infections	250 mg every 8 hours
Amoxicillin-clavulanate	Bites, mixed infections, diabetic ulcers	Higher risk of diarrhea, liver enzyme changes	875 mg every 12 hours
Doxycycline	MRSA, tick-borne infections, acne-related wounds	Not for kids under 8, sun sensitivity	100 mg every 12 hours
Clindamycin	MRSA, deep tissue infections	High risk of C. diff, expensive	300-450 mg every 6-8 hours
Cephalexin	Similar to cefaclor, cheaper	Less effective against some gram-negative bugs	500 mg every 6 hours

What to Watch For After Starting Cefaclor

If you’re on cefaclor for a wound, monitor these signs:

• Redness spreading beyond the original area
• New fever or chills
• Pus returning after drainage
• Wound getting more painful instead of less
• Diarrhea that starts after day 3 of taking the drug

If any of these happen, call your provider. Don’t wait. An infection that doesn’t respond to cefaclor in 48-72 hours likely needs a different antibiotic-or drainage, or imaging to check for deeper problems.

Why Not Just Use the Strongest Antibiotic?

It’s tempting to think stronger means better. But overusing broad-spectrum antibiotics like fluoroquinolones or vancomycin pushes bacteria toward resistance. Cefaclor is narrow enough to spare good bacteria in your gut, yet effective for many common wound bugs.

It’s also cheaper than newer options. A 10-day course of cefaclor costs around $15-$25 at most U.S. pharmacies. Compare that to linezolid ($300+) or daptomycin (not even oral).

Using the right tool for the job-not the most powerful one-is how we keep antibiotics working for everyone.

Final Takeaway

Cefaclor has a real place in wound care-but only in the right hands and the right cases. It’s not magic. It’s not for every infected cut. But for mild skin infections caused by susceptible bacteria, it’s reliable, affordable, and easy to take.

Always pair it with proper wound cleaning, drainage if needed, and follow-up. Antibiotics alone won’t heal a wound. They just help your body do its job.