Zeniquin for Cats & Drowsiness

It's not the Zeniquin -- he always sleeps like this.
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If your cat comes down with some run-of-the-mill infection, it's unlikely your vet will prescribe Zeniquin. If Kitty is diagnosed with a serious bacterial infection, that's another story. Zeniquin might save his life. It might make him drowsy, too. What's a little drowsiness when your pet's health is at stake?


Approved by the U.S. Food and Drug Administration for use in cats in 2002 after previous approval for dogs, Zeniquin is manufactured by Pfizer Animal Health. Zeniquin is the brand name of marbofloxacin, a broad-spectrum antibiotic of the fluoroquinolone class, which inhibits bacteria. Vets prescribe it for cats suffering from bacterial urinary tract infections as well as infections of the skin or soft tissue. An advantage Zeniquin has over other antibiotics is its quick and complete absorption by Kitty's gastrointestinal tract.

Side Effects

The primary side effect noted in clinical studies of Zeniquin is decreased activity. Since most cats spend the better part of their days and nights sleeping, it's a safe bet that the decreased activity results from the drug's tendency to cause drowsiness. Let's face it -- actually measuring drowsiness in a cat isn't that simple. Is Kitty now sleeping 23 hours of the day instead of 22, as he generally does? Since Kitty is unlikely to drive or operate heavy machinery, drowsiness isn't that much of an issue. Other side effects include appetite loss, drooling, vomiting and diarrhea. Kitty might also develop a red rash. Those side effects are a lot more apparent than additional cat naps are.


Zeniquin is available in tablet form, usually given once a day. The coated tablets come in dosages of 25, 50, 100 and 200 milligrams, with the higher dosages used for dogs. Your vet prescribes the specific dosage. According to Drugs.com, the recommended dosage for oral administration for cats is 1.25 milligrams of marbofloxacin per pound of body weight, once daily; but the dosage may be safely increased to 2.5 milligrams per pound.


Your vet won't prescribe Zeniquin if your cat is less than a year old or if he has an otherwise compromised immune system. Pregnant or nursing cats shouldn't get Zeniquin. Epileptic cats or felines with history of neurological problems shouldn't receive the drug. Tell your vet about any other medication or over-the-counter supplements your cat receives, as they might interact with Zeniquin. Milk, vitamins and mineral supplements, for instance, lessen the medication's effectiveness. Giving your kitty antacids may also lower Zeniquin's effectiveness. If you do give milk to your cat, don't give any within a couple of hours of Zeniquin administration, as milk contains minerals.

Always check with your veterinarian before changing your pet’s diet, medication, or physical activity routines. This information is not a substitute for a vet’s opinion.

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