Clavamox for Dogs: Complete Dosage, Side Effects & Safety Guide
Everything dog owners need to know about Clavamox for dogs — dosage by weight, side effects, drug interactions, cost, and when to call your vet.
This medication requires a veterinarian prescription and should only be used under veterinary supervision. Never administer Clavamox (amoxicillin-clavulanate) to your dog without a current prescription from a licensed veterinarian. Incorrect dosing can cause treatment failure, antibiotic resistance, or serious adverse reactions.
What Is Clavamox and What Is It Used for in Dogs?
Clavamox is a brand-name, broad-spectrum antibiotic combining two active ingredients: amoxicillin (a beta-lactam penicillin-type antibiotic) and clavulanate potassium (a beta-lactamase inhibitor). Manufactured by Zoetis, it is one of the most commonly prescribed oral antibiotics in veterinary medicine and is available in both chewable tablet and oral suspension (liquid) forms.
The FDA has approved Clavamox specifically for veterinary use in dogs and cats. The combination formulation exists because many bacteria produce an enzyme called beta-lactamase that destroys amoxicillin alone. Clavulanate neutralizes that enzyme, allowing amoxicillin to do its job — making Clavamox effective against a wider range of bacteria than amoxicillin by itself.
FDA-Approved Uses in Dogs
- Skin and soft tissue infections — wounds, abscesses, cellulitis, dermatitis caused by susceptible bacteria including Staphylococcus species and Streptococcus species
- Periodontal (dental) infections — gingivitis, periodontitis, and oral infections where anaerobic bacteria are common
Common Off-Label (Extra-Label) Uses
Veterinarians frequently prescribe Clavamox for conditions beyond its original FDA label under the Animal Medicinal Drug Use Clarification Act (AMDUCA). These include:
- Urinary tract infections (UTIs) — particularly uncomplicated lower UTIs
- Respiratory infections — bacterial pneumonia, kennel cough with secondary bacterial involvement
- Ear infections (otitis externa/media) — when bacterial culture supports use
- Anal gland abscesses
- Prostate infections (prostatitis)
- Bone infections (osteomyelitis) — as part of a broader treatment plan
- Post-surgical prophylaxis — preventing infection after certain procedures
Important context: According to the Merck Veterinary Manual, potentiated penicillins like amoxicillin-clavulanate are considered first-line choices for many common canine bacterial infections. However, responsible veterinarians increasingly recommend antimicrobial stewardship — performing bacterial culture and sensitivity testing before prescribing, especially for recurrent or complicated infections.
How Does Clavamox Work? Mechanism of Action
Mechanism Explainer
Step 1 — Amoxicillin attacks the cell wall. Amoxicillin belongs to the aminopenicillin group. It works by binding to penicillin-binding proteins (PBPs) inside bacterial cell walls, blocking the cross-linking of peptidoglycan — the structural mesh that gives the wall its strength. Without a functional cell wall, bacteria swell and rupture (bactericidal action).
Step 2 — Clavulanate disarms bacterial defenses. Many resistant bacteria produce beta-lactamase enzymes that break the beta-lactam ring in amoxicillin, rendering it useless. Clavulanate potassium is a structural analog that irreversibly binds to and inactivates these beta-lactamase enzymes — essentially acting as a decoy so amoxicillin can reach its target unharmed.
The result: Clavamox is effective against beta-lactamase-producing strains of Staphylococcus aureus, E. coli, Klebsiella, Proteus, and Bacteroides species that would be resistant to amoxicillin alone.
Clavamox is classified as a time-dependent antibiotic, meaning its effectiveness depends on keeping drug levels above the minimum inhibitory concentration (MIC) for a sufficient portion of the dosing interval. This is why consistent twice-daily dosing matters more than giving a single large dose.
Clavamox Dosage for Dogs by Weight and Condition
The standard dosage of Clavamox for dogs is 6.25 mg per pound (13.75 mg/kg) of body weight, given orally every 12 hours. This is the combined amoxicillin + clavulanate dose. Your veterinarian will determine the exact dose based on your dog's weight, the type and severity of infection, and any comorbidities.
Consult your veterinarian before making any dosage decisions. The table below reflects standard published dosing ranges for educational purposes — your vet's prescribed dose may differ based on clinical judgment.
| Dog Weight | Dose per Administration | Daily Total | Common Tablet Size |
|---|---|---|---|
| 5 lb (2.3 kg) | 31.25 mg | 62.5 mg | 62.5 mg tablet (half) |
| 10 lb (4.5 kg) | 62.5 mg | 125 mg | 62.5 mg tablet (whole) |
| 15 lb (6.8 kg) | 93.75 mg | 187.5 mg | 125 mg tablet |
| 25 lb (11.3 kg) | 156.25 mg | 312.5 mg | 125 mg tablet |
| 40 lb (18.1 kg) | 250 mg | 500 mg | 250 mg tablet |
| 60 lb (27.2 kg) | 375 mg | 750 mg | 375 mg tablet |
| 80 lb (36.3 kg) | 500 mg | 1000 mg | 375 mg tablet (adjust) |
| 100 lb (45.4 kg) | 625 mg | 1250 mg | 375 mg + 250 mg |
Dosage Adjustments by Condition
While the standard dose remains 6.25 mg/lb BID for most indications, your veterinarian may adjust the protocol depending on the infection type:
- Uncomplicated skin infections: Standard dose, 7–10 day course
- Deep or complicated skin infections (pyoderma): Standard dose, 21–28+ day course — often continued 7 days beyond clinical resolution
- Urinary tract infections: Standard dose, 7–14 day course; some vets dose at the higher end (up to 9 mg/lb BID) for upper UTIs or pyelonephritis
- Dental/periodontal infections: Standard dose, 7–10 day course, often combined with professional dental cleaning
- Respiratory infections: Standard to high-end dose, 10–21 day course depending on severity
- Osteomyelitis (bone infection): Higher doses, extended courses of 4–8 weeks or longer, often combined with surgical debridement
How to Administer Clavamox to Your Dog
Clavamox is available in two formulations, and proper administration affects both compliance and effectiveness:
Chewable Tablets
- The chewable tablets are beef-and-pork flavored and most dogs accept them readily as a treat
- Can be given with or without food, but giving with a small meal reduces the risk of gastrointestinal upset (the most common side effect)
- If your dog refuses the chewable, you can hide it in a small amount of peanut butter (xylitol-free), cream cheese, or a pill pocket
- Do not crush and mix into a full bowl of food — if your dog doesn't finish the meal, they receive an incomplete dose
Oral Suspension (Liquid)
- Available in 62.5 mg/mL concentration after reconstitution
- The bottle must be refrigerated after mixing and is stable for 10 days
- Shake well before each dose to ensure even distribution
- Use the provided dosing syringe or a calibrated oral syringe — household teaspoons are inaccurate
- Administer into the cheek pouch, not directly down the throat, to prevent aspiration
Duration: How Long Does My Dog Need to Be on Clavamox?
This is one of the most common questions owners ask, and the answer depends entirely on the infection. A general principle in veterinary antimicrobial therapy: treat until the infection is clinically resolved, then continue for an additional 5–7 days. Stopping early — even if your dog looks better — risks incomplete eradication and development of antibiotic-resistant bacteria.
| Condition | Typical Duration | Follow-Up Needed? |
|---|---|---|
| Simple UTI | 7–14 days | Urinalysis 5–7 days post-treatment |
| Superficial skin infection | 7–14 days | Recheck if not improving in 48–72 hours |
| Deep pyoderma | 21–42 days | Yes — recheck every 2 weeks |
| Dental infection | 7–10 days | Post-dental cleaning check |
| Ear infection (otitis) | 10–21 days | Cytology recheck before stopping |
| Respiratory infection | 10–21 days | Recheck if cough persists past 7 days |
| Bone infection | 4–8+ weeks | Radiographs + bloodwork monitoring |
Clavamox Side Effects: What to Watch For
Like all antibiotics, Clavamox can cause side effects. Most are mild and gastrointestinal in nature. Serious reactions are uncommon but require immediate attention.
| Side Effect | Estimated Frequency | Severity | What to Do |
|---|---|---|---|
| Vomiting | 10–15% | Mild | Give with food; contact vet if persistent (>2 episodes) |
| Diarrhea / loose stools | 10–20% | Mild–Moderate | Add probiotic (2 hrs apart from dose); call vet if bloody or lasts >48 hrs |
| Decreased appetite | 5–10% | Mild | Monitor; offer bland diet; call vet if not eating for >24 hrs |
| Drooling (bitter taste) | 5–8% (liquid form) | Mild | Follow with water or treat; usually resolves |
| Allergic reaction (hives, facial swelling) | <2% | Serious | Stop medication and contact vet immediately |
| Anaphylaxis (collapse, difficulty breathing) | <0.1% | Emergency | Emergency vet immediately — life-threatening |
| Severe watery/bloody diarrhea (possible C. diff) | <1% | Serious | Stop medication and contact vet immediately |
- Facial swelling, hives, or itching that appears suddenly after a dose
- Difficulty breathing, wheezing, or collapse
- Vomiting that persists more than 24 hours or prevents keeping the medication down
- Bloody or severe watery diarrhea
- Yellowing of gums or eyes (possible liver involvement — rare but serious)
- Seizures (extremely rare, associated with very high doses or renal impairment)
- Your dog seems unusually lethargic or unresponsive
Probiotics and Antibiotic-Associated Diarrhea
Antibiotic-associated diarrhea occurs because Clavamox disrupts normal gut flora along with pathogenic bacteria. Many veterinarians recommend adding a canine-specific probiotic such as FortiFlora (Purina) or Proviable (Nutramax) during the antibiotic course. The key timing rule: give the probiotic at least 2 hours apart from the Clavamox dose, otherwise the antibiotic will kill the beneficial bacteria in the probiotic before they reach the gut.
Contraindications and Drug Interactions
Dogs Who Should NOT Receive Clavamox
- Known penicillin or cephalosporin allergy: Dogs with a documented hypersensitivity to any beta-lactam antibiotic should not receive Clavamox. Cross-reactivity between penicillins and cephalosporins occurs in approximately 5–10% of allergic patients.
- History of anaphylaxis to any antibiotic: Even if the prior reaction was to a different drug class, your vet will weigh the risk carefully.
- Severe kidney disease: Amoxicillin is primarily excreted through the kidneys. Dogs with significantly reduced renal function may require dose reduction or extended dosing intervals to prevent toxic accumulation.
- Very small or neonatal puppies: Immature kidney function in puppies under 4–6 weeks may affect drug clearance. Your veterinarian will determine if the benefits outweigh risks.
Drug Interaction Grid
| Medication | Interaction Type | Clinical Significance | Management |
|---|---|---|---|
| Bacteriostatic antibiotics (tetracycline, chloramphenicol, erythromycin) | Antagonistic | Moderate — bacteriostatic drugs slow bacterial growth, reducing amoxicillin's effectiveness (which requires actively dividing cells) | Avoid concurrent use unless specifically directed by your vet |
| Methotrexate | Increased toxicity | High — penicillins reduce renal clearance of methotrexate | Avoid combination; use alternative antibiotic |
| Probenecid | Increased amoxicillin levels | Moderate — probenecid blocks renal tubular secretion, raising amoxicillin blood levels | Dose adjustment may be needed; vet monitoring required |
| Oral bacterin vaccines (e.g., oral Bordetella vaccine) | Reduced vaccine efficacy | Moderate — antibiotics may kill live bacterial vaccine organisms | Delay vaccination until antibiotic course is complete |
| Mycophenolate | Reduced immunosuppressant levels | Low–Moderate — amoxicillin may reduce enterohepatic recirculation of mycophenolate | Monitor drug levels if concurrent use is necessary |
| Aminoglycosides (gentamicin, amikacin) | Synergistic (positive interaction) | Beneficial — combination can enhance bacterial killing for serious infections | Often intentionally combined for severe infections under vet supervision |
Always provide your veterinarian with a complete list of every medication, supplement, and over-the-counter product your dog is currently receiving before starting Clavamox. This includes flea/tick preventives, joint supplements, herbal remedies, and any other prescriptions.
Monitoring, Follow-Up, and What to Expect
Most uncomplicated infections treated with Clavamox don't require extensive monitoring — but certain situations call for closer veterinary follow-up.
Monitoring Schedule
48–72 hours after starting: You should see noticeable improvement in your dog's symptoms. If there is no improvement or symptoms worsen, contact your veterinarian — the bacteria may be resistant, or the diagnosis may need reassessment.
Mid-course (for infections lasting >14 days): A recheck exam is typically recommended. Your vet may perform:
- Physical exam to assess clinical response
- Cytology or culture (for ear, skin, or urinary infections) to confirm bacterial clearance
- Blood work (CBC, chemistry panel) if your dog has pre-existing kidney or liver conditions
End of course (5–7 days after last dose): For UTIs, a follow-up urinalysis and possibly a urine culture are standard to confirm the infection has been fully cleared. For deep skin infections, your vet will examine the skin to determine if the course needs extending.
Long-term or recurrent infections: If your dog has had 3 or more infections in a 12-month period, your veterinarian will likely recommend:
- Bacterial culture and sensitivity (C&S) testing — costs approximately $80–$180 depending on the lab
- Investigation of underlying causes (allergies, immune disorders, anatomical abnormalities, endocrine disease)
- Referral to a veterinary dermatologist or internal medicine specialist
Missed Doses, Overdose, and Storage
What to Do If You Miss a Dose
Give the missed dose as soon as you remember — unless it is nearly time for the next scheduled dose. In that case, skip the missed dose and resume the normal schedule. Never double the dose to make up for a missed one. Doubling increases the risk of vomiting, diarrhea, and in rare cases, neurological side effects.
Occasional missed doses are unlikely to cause treatment failure, but frequent missed doses reduce the time-dependent antibiotic effect and can allow bacteria to recover and develop resistance. If you are struggling with compliance, ask your veterinarian about:
- Switching to a once-daily antibiotic alternative (e.g., Convenia/cefovecin injection, which lasts 14 days per dose)
- Using a pill organizer or phone alarm reminders
- Switching from liquid to chewable tablet (or vice versa) for easier administration
Overdose: Signs and What to Do
Clavamox has a wide safety margin, and mild overdoses (e.g., accidentally giving a double dose) typically cause only gastrointestinal signs — vomiting, diarrhea, and possibly drooling. However, significant overdoses can be more serious.
- Do not induce vomiting unless specifically instructed by a veterinarian.
- Call your veterinarian or emergency veterinary clinic immediately.
- Call ASPCA Animal Poison Control: (888) 426-4435 (24/7, consultation fee applies) or Pet Poison Helpline: (855) 764-7661 for guidance.
- Have the medication bottle/package available to provide the exact strength and amount ingested.
- Monitor for vomiting, diarrhea, lethargy, tremors, or seizures.
Storage Requirements
- Chewable tablets: Store at room temperature (68–77°F / 20–25°C) in the original container, away from moisture and direct sunlight. Keep out of reach — the flavored tablets can smell like treats to dogs.
- Oral suspension (reconstituted): Must be refrigerated (36–46°F / 2–8°C). Discard any unused suspension after 10 days. Do not freeze.
Cost of Clavamox and Generic Alternatives
Clavamox is available as a brand-name product from Zoetis and as generic amoxicillin-clavulanate potassium from multiple manufacturers. Generic versions are FDA-approved and therapeutically equivalent.
| Product | Form | Typical Price Range | Notes |
|---|---|---|---|
| Clavamox (brand) chewable tablets | 62.5 mg, 125 mg, 250 mg, 375 mg (per tablet) | $1.50–$3.50 per tablet | Sold in 100-count bottles through veterinary pharmacies |
| Generic amoxicillin-clavulanate tablets | Same strengths | $0.50–$1.80 per tablet | Available through online veterinary pharmacies (Chewy, 1-800-PetMeds) with vet authorization |
| Clavamox (brand) oral suspension | 62.5 mg/mL, 15 mL bottle | $18–$32 per bottle | Must be reconstituted by pharmacy; 10-day shelf life after mixing |
| Generic amoxicillin-clavulanate suspension | 62.5 mg/mL, 15 mL bottle | $12–$22 per bottle | Same storage and shelf life requirements |
Cost-saving tips:
- Ask your veterinarian to write a prescription you can fill at an online veterinary pharmacy — this can save 30–50% compared to in-clinic dispensing
- Request generic amoxicillin-clavulanate rather than brand-name Clavamox — the active ingredients and efficacy are identical
- For a 50 lb dog on a standard 10-day course (250 mg BID), expect to pay roughly $15–$35 with generics or $30–$70 with brand-name Clavamox
- Some veterinary clinics offer price-matching with verified online pharmacies
Are There Alternatives to Clavamox?
Yes — depending on the infection type, bacterial susceptibility, and your dog's individual health factors, your veterinarian may consider alternatives. The choice of antibiotic should ideally be guided by bacterial culture and sensitivity results, not just convenience.
| Antibiotic | Drug Class | When It's Preferred | Typical Cost (10-day course, 50 lb dog) |
|---|---|---|---|
| Cephalexin | 1st-gen cephalosporin | Skin infections (pyoderma); first-line per AVMA stewardship guidelines | $10–$25 (generic) |
| Convenia (cefovecin) | 3rd-gen cephalosporin injection | Dogs difficult to pill; single injection lasts 14 days | $60–$120 per injection (clinic-administered) |
| Enrofloxacin (Baytril) | Fluoroquinolone | Gram-negative infections, UTIs, prostate infections; reserved per stewardship | $20–$45 (generic) |
| Doxycycline | Tetracycline | Tick-borne diseases, respiratory infections, leptospirosis | $10–$30 (generic) |
| Metronidazole | Nitroimidazole | Anaerobic infections, giardia, some dental infections | $10–$25 (generic) |
| Simplicef (cefpodoxime) | 3rd-gen cephalosporin | Skin infections, wounds; once-daily dosing convenience | $25–$55 (generic available) |
Your veterinarian will choose based on the specific bacteria involved, infection location, your dog's organ function, ease of administration, and antimicrobial stewardship principles. The goal is always to use the narrowest-spectrum antibiotic effective against the identified pathogen, reserving broader-spectrum options like Clavamox for situations where they are truly needed.
Frequently Asked Questions About Clavamox
Can I give my dog human amoxicillin-clavulanate (Augmentin)?
While the active ingredients are the same, you should never give your dog human Augmentin without explicit veterinary direction. The tablet strengths differ (human Augmentin comes in 250/125, 500/125, and 875/125 mg ratios), and the amoxicillin-to-clavulanate ratio in human formulations may not match the veterinary-approved 4:1 ratio in Clavamox. Incorrect ratios can cause excessive clavulanate exposure (increasing diarrhea risk) or insufficient clavulanate (reducing effectiveness). Additionally, some human liquid formulations contain xylitol, which is toxic to dogs.
Can Clavamox be given to pregnant or nursing dogs?
Amoxicillin is generally considered safe during pregnancy and lactation in dogs — it is classified as a low-risk drug for use in pregnant animals. However, clavulanate has less reproductive safety data. Your veterinarian will evaluate whether the combination is appropriate or if amoxicillin alone would suffice for a pregnant or nursing dog.
My dog is on Clavamox and has diarrhea — should I stop the medication?
Mild, soft stools are common and usually not a reason to stop the antibiotic. Try giving the medication with food and adding a canine probiotic (spaced 2 hours apart). However, if the diarrhea is watery, bloody, accompanied by vomiting, or persists beyond 48 hours, contact your veterinarian before discontinuing — stopping antibiotics prematurely can lead to treatment failure and resistant infections.
How quickly does Clavamox start working?
Most dogs begin showing improvement within 24–48 hours of starting Clavamox. You may notice reduced swelling, less discharge, improved energy, or decreased pain. Full resolution takes the entire course. If there is no improvement after 72 hours, the bacteria may be resistant, and your vet may want to perform a culture and sensitivity test.
Can Clavamox cause yeast infections in dogs?
Yes. By disrupting normal bacterial flora on the skin and in the ears, Clavamox can create an environment where Malassezia yeast overgrows. Signs include increased scratching, a musty or "corn chip" odor, redness in the ears, and greasy skin. If you notice these signs during or after a Clavamox course, your vet can prescribe an antifungal shampoo, ear cleaner, or oral medication.
Is Clavamox safe for all dog breeds?
Clavamox is safe for all recognized dog breeds — there are no breed-specific contraindications as there are with some other drugs (e.g., ivermectin sensitivity in MDR1 gene carriers). However, individual dogs of any breed can have an allergic reaction to penicillin-type antibiotics. Always monitor your dog closely during the first 24–48 hours of any new medication.
A final note on responsible antibiotic use: The FDA's Veterinary Antimicrobial Stewardship initiative emphasizes that antibiotics like Clavamox should be used judiciously — only when a bacterial infection is confirmed or strongly suspected, at the correct dose, for the appropriate duration. Overuse and misuse of antibiotics contributes to the growing problem of antimicrobial resistance, which threatens both animal and human health. Always follow your veterinarian's complete treatment plan and attend all recommended follow-up appointments.
Anouk Beaumont
All our authors care for dogs every day — read more of their work on the authors page.
