Kanamycin Sulfate

Aminoglycoside Antibiotic Antibacterial

Dosage & Administration Guidelines

Species Route Dose Frequency Duration & Clinical Notes
Dog IM/SC 10-15 mg/kg q8h Duration: 5-7 days
Notes: Monitor renal function; adjust dose in renal impairment.
Cat IM/SC 10-15 mg/kg q8h Duration: 5-7 days
Notes: Monitor renal function; adjust dose in renal impairment.
Horse IV/IM 5-10 mg/kg q8-12h Duration: 5-7 days
Notes: Use with caution; monitor renal function and hydration.
Cattle IM/SC 10-15 mg/kg q12h Duration: 3-5 days
Notes: Observe withdrawal times; not for use in lactating dairy cows if milk withdrawal is not followed.
Small Ruminants (sheep/goats) IM/SC 10-15 mg/kg q12h Duration: 3-5 days
Notes: Extra-label use; observe withdrawal times.
Rabbit SC/IM 10-15 mg/kg q8-12h Duration: 5-7 days
Notes: High risk of nephrotoxicity; use only if no alternative; ensure adequate hydration.
Birds/Poultry IM/SC 10-20 mg/kg q8-12h Duration: 3-5 days
Notes: Use with caution; monitor hydration.
Reptiles IM 5-10 mg/kg q24-48h Duration: 5-7 days
Notes: Dosing interval may be prolonged due to lower metabolic rates.

Clinical Indications & Species Uses

General Indications
  • Treatment of infections caused by susceptible Gram-negative bacteria when less toxic alternatives are not available or appropriate
Dog (Canine)
  • Treatment of infections caused by susceptible Gram-negative bacteria, including urinary tract infections, respiratory infections, skin infections, and septicemia
  • Ophthalmic infections (topical preparations)
Cat (Feline)
  • Treatment of susceptible Gram-negative bacterial infections, including urinary tract infections, respiratory infections, and skin infections
  • Intestinal infections (oral administration for local effect)
Horse (Equine)
  • Treatment of susceptible Gram-negative bacterial infections, including respiratory infections, septicemia, and joint infections (in combination with other therapy)
  • Intrauterine infusion for metritis
Cattle (Bovine)
  • Treatment of susceptible Gram-negative bacterial infections, including respiratory disease (e.g., pneumonia), septicemia, and enteric infections
  • Intrauterine infusion for metritis
Small Ruminants (Sheep / Goat)
  • Treatment of susceptible Gram-negative bacterial infections, including respiratory and enteric infections
Rabbit & Small Mammals
  • Treatment of susceptible Gram-negative bacterial infections, particularly respiratory infections (e.g., Pasteurella multocida) - use with caution due to nephrotoxicity
Avian & Poultry
  • Treatment of susceptible Gram-negative bacterial infections, including colibacillosis and salmonellosis (oral or injectable)
Exotic & Other Species
  • Reptiles: Treatment of susceptible Gram-negative infections; Small mammals (e.g., ferrets, guinea pigs): Treatment of susceptible infections, but use with caution due to nephrotoxicity

Pharmacology & Mechanism of Action

Drug Class: Aminoglycoside Antibiotic | Pharmacological Group: Antibacterial

Mechanism of Action: Kanamycin is an aminoglycoside antibiotic that exerts its bactericidal effect by binding irreversibly to the 30S ribosomal subunit of susceptible bacteria. This binding interferes with the initiation of protein synthesis, causing misreading of the genetic code and production of nonfunctional or toxic proteins. This leads to disruption of the bacterial cell membrane and eventual cell death. Kanamycin is primarily active against aerobic Gram-negative bacteria and some Gram-positive organisms, but it is less effective against Pseudomonas aeruginosa compared to other aminoglycosides like gentamicin. Its action is concentration-dependent and exhibits a post-antibiotic effect.

Pharmacodynamics: Kanamycin exhibits rapid, concentration-dependent bactericidal activity. It is effective against a broad spectrum of aerobic Gram-negative bacteria including Escherichia coli, Klebsiella spp., Proteus spp., Salmonella spp., and some strains of Staphylococcus aureus. It has limited activity against Gram-positive cocci and is ineffective against anaerobes, fungi, and viruses. The minimum inhibitory concentration (MIC) for susceptible organisms is typically ≤ 16 µg/mL. Resistance can occur through plasmid-mediated enzymes that modify the drug, reducing its affinity for the ribosome. Kanamycin is more active at alkaline pH and its activity is reduced in acidic environments, such as in abscesses or in the presence of purulent material.

⚡ Pharmacokinetics Summary

Absorption: Kanamycin is poorly absorbed from the gastrointestinal tract after oral administration, with bioavailability typically less than 1%. However, in neonates or animals with compromised intestinal mucosa, absorption may be increased. After intramuscular (IM) or subcutaneous (SC) injection, absorption is rapid and complete, with peak serum concentrations achieved within 30-60 minutes. Intravenous (IV) administration provides immediate peak levels.
Distribution: Kanamycin is a polar, water-soluble compound that distributes primarily into the extracellular fluid. It penetrates poorly into the cerebrospinal fluid, eye, and prostate. It does cross the placenta and can accumulate in fetal tissues. High concentrations are achieved in the renal cortex, where it can cause nephrotoxicity. It also distributes into synovial, pleural, and peritoneal fluids, but concentrations are lower than serum levels. Protein binding is low (less than 10%).
Metabolism: Kanamycin undergoes minimal metabolism in the body. It is not significantly biotransformed and is excreted largely unchanged.
Excretion: Kanamycin is excreted primarily by glomerular filtration in the kidneys, with over 90% of an administered dose recovered in the urine within 24 hours. In animals with normal renal function, the elimination half-life is approximately 2-4 hours in dogs and cats, but it can be significantly prolonged in neonates or animals with renal impairment. Biliary excretion is minimal.
Half-Life: Dogs: 1.5-2 hours; Cats: 1-2 hours; Horses: 1.5-3 hours; Cattle: 2-3 hours; prolonged in renal impairment.
Bioavailability: Oral: <1%; IM/SC: nearly 100%
Protein Binding: Less than 10%

Available Formulations & Strengths

Injectable Solution 200 mg/mL, 500 mg/mL (IM, SC, IV (slow))
Oral Solution 50 mg/mL (for intestinal infections) (PO)
Ophthalmic Solution/Ointment 0.5% solution, 0.5% ointment (Ophthalmic)
Powder for Oral Solution Various (e.g., 100 g per bottle) (PO)

Contraindications & Clinical Warnings

Contraindications:
  • Hypersensitivity to kanamycin or other aminoglycosides
  • Pre-existing renal disease or severe renal impairment
  • Dehydration or hypovolemia (increases risk of nephrotoxicity)
  • Concurrent use of other nephrotoxic drugs (e.g., amphotericin B, cyclosporine, NSAIDs)
  • Concurrent use of neuromuscular blocking agents (may enhance neuromuscular blockade)
  • Use in animals with myasthenia gravis or other neuromuscular disorders
Warnings & Clinical Precautions:
  • Use with caution in neonates and geriatric animals due to immature or declining renal function.
  • Monitor renal function (serum creatinine, BUN) and urine output before and during therapy.
  • Ensure adequate hydration to reduce risk of nephrotoxicity.
  • Avoid prolonged therapy (>7 days) unless necessary.
  • May cause ototoxicity (both auditory and vestibular) which can be irreversible.
  • Use with caution in animals with hepatic impairment (though not primarily hepatically metabolized).
  • In food animals, observe withdrawal times to avoid violative residues.
  • Do not mix with other drugs in the same syringe or infusion line (incompatibility).
  • In horses, avoid intra-articular injection unless absolutely necessary due to risk of cartilage damage.

Adverse Effects & Reactions

Common:

  • Nephrotoxicity (increased BUN/creatinine, proteinuria, casts)
  • Ototoxicity (hearing loss, vestibular signs such as ataxia, head tilt)
  • Gastrointestinal upset (nausea, vomiting, diarrhea) after oral administration
  • Pain at injection site

Serious / Severe:

  • Acute renal failure
  • Irreversible ototoxicity
  • Neuromuscular blockade leading to respiratory depression
  • Anaphylaxis (rare)

Rare:

  • Allergic reactions (rash, fever, eosinophilia)
  • Hepatotoxicity (rare)
  • Electrolyte disturbances (hypokalemia, hypocalcemia)

Key Drug Interactions

Interacting Drug / Class Clinical Effect & Mechanism Severity
Other aminoglycosides (e.g., gentamicin, amikacin) Additive nephrotoxicity and ototoxicity High
Loop diuretics (e.g., furosemide) Increased risk of ototoxicity and nephrotoxicity High
Neuromuscular blocking agents (e.g., atracurium, succinylcholine) Enhanced neuromuscular blockade, respiratory depression High
Nonsteroidal anti-inflammatory drugs (NSAIDs) Increased risk of nephrotoxicity due to reduced renal blood flow Moderate
Polymyxin B Additive nephrotoxicity and neuromuscular blockade High
Cephalosporins (especially first-generation) Additive nephrotoxicity Moderate
Methoxyflurane (anesthetic) Increased risk of nephrotoxicity Moderate

Overdose & Toxicity Management

Signs of Toxicity:

  • Acute renal failure (oliguria, anuria, elevated BUN/creatinine)
  • Ototoxicity (hearing loss, ataxia, nystagmus)
  • Neuromuscular blockade (muscle weakness, respiratory depression)
  • Gastrointestinal signs (vomiting, diarrhea) after oral overdose

Emergency Treatment Protocol: There is no specific antidote. Treatment is supportive and symptomatic. Discontinue the drug immediately. Maintain adequate hydration with intravenous fluids to promote renal excretion. Monitor renal function and electrolytes. In severe cases, hemodialysis or peritoneal dialysis may be considered to remove the drug. For neuromuscular blockade, administer calcium salts (e.g., calcium gluconate) and neostigmine (with atropine) to reverse the effects. Provide respiratory support if needed.

Food Animal Withdrawal Times

🥩 Meat: 18 days🥛 Milk: 48 days

Withdrawal times vary by country and formulation. In the US, the label withdrawal time for cattle is 18 days for meat and 48 hours for milk (if used according to label). For extra-label use, consult FARAD (Food Animal Residue Avoidance Databank). For poultry, withdrawal time is typically 5-7 days for meat, but check specific product label.

Storage, Handling & Regulatory Information

Storage Temperature: Store at controlled room temperature 20-25°C (68-77°F), protect from freezing.

Light Sensitivity: Light-sensitive — protect from direct exposure.

Handling & Special Conditions: Protect from light. Keep container tightly closed. Avoid excessive heat. Do not use if solution is discolored or contains particulate matter.

Dispensing Status: Prescription Required (Rx Only)

Approval Status: Approved for veterinary use in dogs, cats, and cattle (injectable). Oral and ophthalmic formulations may be approved for certain species. Not approved for use in horses or other food animals, but may be used extra-label.

Extra-Label (Off-Label) Use: In the US, kanamycin is approved for use in dogs, cats, and cattle. Extra-label use in other species or at different doses is permitted under AMDUCA (Animal Medicinal Drug Use Clarification Act) with a valid veterinary-client-patient relationship, but requires extended withdrawal times. In food animals, extra-label use is prohibited if there is an approved drug that is labeled for the condition and species, unless the veterinarian determines it is ineffective. Consult FARAD for withdrawal interval recommendations.

Clinical Pearls & Practice Notes

💡 Clinical Insights: Kanamycin is an older aminoglycoside that is less commonly used today due to the availability of safer and more effective alternatives such as amikacin and gentamicin. It is primarily used for infections caused by susceptible Gram-negative bacteria when other antibiotics are ineffective or contraindicated. Because of its significant nephrotoxic and ototoxic potential, it should be reserved for serious infections and used with caution, especially in animals with renal impairment or dehydration. Therapeutic drug monitoring is recommended if available, aiming for peak serum concentrations of 20-30 µg/mL and trough levels below 5 µg/mL to minimize toxicity. In food animals, strict adherence to withdrawal times is essential. For topical ophthalmic use, kanamycin is sometimes combined with other antibiotics (e.g., in triple antibiotic ophthalmic preparations). Overall, kanamycin should be considered a second-line agent in veterinary practice.

References & Literature

  • 📚 Plumb's Veterinary Drug Handbook
  • 📚 Papich Veterinary Pharmacology and Therapeutics
  • 📚 Compendium of Veterinary Products (CVP)