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Clarithromycin

Prescription

Macrolide Antibiotic

Last reviewed 21 Apr 2026 · PetCare.AI Editorial Team

Species

Dog, Cat

Brands

1 available

Interactions

4 documented

Formulations

Mechanism of action

Semisynthetic macrolide that binds 50S ribosomal subunit inhibiting protein synthesis. Better acid stability than erythromycin. Active against Mycobacterium, Helicobacter, Bartonella, and atypical organisms.

At a glance

Class

Macrolide Antibiotic

Schedule

Prescription

Storage

Store at room temperature; suspension — do not refrigerate, use within 14 days

Dosing

🐕

Dog

Used for mycobacterial infections, Helicobacter (triple therapy), and Bartonella

Dose

5–10 mg/kg

Route

Frequency

q12h

🐈

Cat

Used for feline mycobacterial infections, Bartonella, and Helicobacter

Dose

7.5 mg/kg

Route

Frequency

q12h

Educational reference only

This information is provided for educational purposes and is not a substitute for professional veterinary advice, diagnosis, or treatment. Always consult a qualified veterinarian before administering any medication to your pet. Find a vet near you →

Formulations

💊

Other — 3

Strength

—

Strength

—

Strength

—

Storage

Store at room temperature; suspension — do not refrigerate, use within 14 days

Safety

Monitoring parameters

GI toleranceHepatic enzymes with prolonged useDrug interaction review

Educational reference only

Interactions

Contraindicated — 1

Cisapride

contraindicated

Clarithromycin potently inhibits CYP3A4 metabolism of cisapride, causing dangerous QT prolongation and torsades de pointes.

Management: NEVER combine. Use metoclopramide as alternative prokinetic.

Major — 2

Cyclosporine (Systemic)

major

Clarithromycin potently inhibits CYP3A4, increasing cyclosporine levels 2-3 fold. More potent CYP inhibitor than azithromycin.

Management: Avoid if possible. If needed, reduce cyclosporine dose by 50% and monitor trough levels closely.

Colchicine

major

Clarithromycin potently inhibits CYP3A4 and P-glycoprotein, causing dangerous colchicine accumulation. Fatal interactions documented in humans.

Management: Avoid. Use alternative antibiotic. If essential, reduce colchicine dose significantly and monitor CBC.

Moderate — 1

Digoxin

moderate

Clarithromycin inhibits P-glycoprotein and may alter gut flora that inactivates digoxin, increasing digoxin levels by 50-100%.

Management: Monitor digoxin levels. Consider reducing digoxin dose by 25-50% during clarithromycin course.

Educational reference only

Brands

Other markets

Biaxin

FAQs

Frequently asked questions

›What is Clarithromycin?

Clarithromycin is a macrolide antibiotic used in pets. Semisynthetic macrolide that binds 50S ribosomal subunit inhibiting protein synthesis. Better acid stability than erythromycin. Active against Mycobacterium, Helicobacter, Bartonella, and atypical organisms.

›What is Clarithromycin used for in pets?

Clarithromycin is used in veterinary medicine for: Used for mycobacterial infections, Helicobacter (triple therapy), and Bartonella; Used for feline mycobacterial infections, Bartonella, and Helicobacter.

›What is the Clarithromycin dose for dogs?

For dogs, Clarithromycin is typically dosed as follows — Used for mycobacterial infections, Helicobacter (triple therapy), and Bartonella: 5–10 mg/kg PO q12h. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.

›What is the Clarithromycin dose for cats?

For cats, Clarithromycin is typically dosed as follows — Used for feline mycobacterial infections, Bartonella, and Helicobacter: 7.5 mg/kg PO q12h. Always consult your veterinarian for a dose tailored to your pet's weight, age, and condition.

›Does Clarithromycin need a prescription?

Yes. Clarithromycin is a prescription medication and should only be administered under veterinary supervision.

Educational reference only