Is this dose of cephalexin okay for my dog?

Our question this week was:

My vet put my great Dane on cephalexin 500 mg 4 pills 3 times a day for 10 days is that too much?


Rick Shambaugh


Hi – thanks for your email Rick. There is a dosage range for cephalexin. The dose can vary slightly depending on the condition being treated and I'd recommend following your veterinarians recommendations.

The dosage range for cephalexin (Keflex®) is most often 22 to 33 mg/kg. Great Danes are big dogs as you know (weight range can be 110 to 160 pounds). Let's say your dog weighs a modest 110 pounds. They would be roughly 55 kg. 55 kg x 22 mg/kg = 1210 mg or if they used the 33 mg/kg = 1815 mg.

Even if you have a small Great Dane, at the higher dose, 2000 mg is closest (since they are using 500 mg capsules). There is a large margin of safety with this drug. I think the dose is okay.

If your dog weighs 150 pounds, then the dosage range would be 1500 mg to 2200 mg.

If you are still concerned, feel free to double check with your veterinarian. Drug errors can occur anywhere so it is always better to be safe than sorry.

An article that might be helpful to you is Cephalexin (Keflex®) Drug Profile.

Best of luck!

Dr. Debra

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