Cephalexin
Also known as: Keflex, Ceporex, Cefalexina, Cefaseptin, Cephacare, Cephorum, Rilexine, Therios, Tsefalen
**Cephalexin** is a commonly prescribed antibiotic used to treat bacterial infections, especially skin infections (pyoderma). * **Administration**: Can be given with or without food. **If your pet vomits or acts sick after receiving the dose, try giving it with a small meal or treat.** * **Finish the Course**: It is critical to give the medication for the entire time prescribed by your veterinarian, even if your pet seems completely better. Stopping early can lead to resistant infections. * **Allergic Reactions**: Though rare, allergic reactions can occur. Contact your veterinarian immediately if you notice facial swelling, hives, severe scratching, sudden diarrhea, or difficulty breathing. * **Storage**: Store capsules and tablets at room temperature. If you were given a liquid suspension, follow the storage instructions on the bottle (usually stable for 14 days after mixing).
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- For superficial and deep pyoderma
- For recurrent pyoderma
- For superficial canine pyoderma
- For pyoderma
- For respiratory infections
- For soft tissue infections
- For systemic infections
- For orthopedic infections
- For pyometra/metritis
- For UTI
- For neonates
- For juvenile cellulitis in 3-16 week old puppies
- For treating infectious otitis
- Susceptible infections (standard dose)
How it is given
Possible side effects
- Gastrointestinal upset (anorexia, vomiting, diarrhea)
- Hypersensitivity reactions (rashes, fever, eosinophilia, anaphylaxis)
- Salivation, tachypnea, and excitability (reported in dogs)
- Emesis and fever (reported in cats)
- Nephrotoxicity (rare)
- Toxic epidermal necrolysis (rarely reported in cats)
- Antibiotic-associated diarrhea or gut flora alteration
Cautions & contraindications
- Known hypersensitivity to cephalosporins
- Patients with septicemia, shock, or grave illness (oral absorption is unreliable; parenteral routes preferred)
- > **Hypersensitivity Cross-Reactivity**: Use with caution in patients with documented hypersensitivity to other beta-lactam antibiotics (e.g., penicillins, carbapenems), as cross-reactivity can occur. * **Renal Impairment**: Use cautiously and consider dose reduction in patients with renal dysfunction or those receiving concurrent nephrotoxic drugs. * **Critically Ill Patients**: Do not use oral systemic antibiotics in patients with shock or septicemia due to delayed or diminished GI absorption. * **Laboratory Interference**: May cause false-positive urine glucose tests (with cupric sulfate solutions like Clinitest) and falsely elevated serum/urine creatinine (with Jaffe reaction).
Drug interactions
- Probenecid: Competitively blocks the tubular secretion of cephalosporins, thereby increasing serum levels and prolonging serum half-lives.
- Aminoglycosides: Increased risk of nephrotoxicity. Do not mix in the same syringe.
- Amphotericin B: Increased risk of nephrotoxicity.
- Loop diuretics (e.g., furosemide): Increased risk of nephrotoxicity.
Frequently asked questions
What is Cephalexin used for in pets?
**Cephalexin** is a commonly prescribed antibiotic used to treat bacterial infections, especially skin infections (pyoderma). * **Administration**: Can be given with or without food. **If your pet vomits or acts sick after receiving the dose, try giving it with a small meal or treat.** * **Finish the Course**: It is critical to give the medication for the entire time prescribed by your veterinarian, even if your pet seems completely better. Stopping early can lead to resistant infections. * **Allergic Reactions**: Though rare, allergic reactions can occur. Contact your veterinarian immediately if you notice facial swelling, hives, severe scratching, sudden diarrhea, or difficulty breathing. * **Storage**: Store capsules and tablets at room temperature. If you were given a liquid suspension, follow the storage instructions on the bottle (usually stable for 14 days after mixing).
Is Cephalexin safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
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