PetMD Editorial
By PetMD Editorial on Nov. 7, 2012

Drug Info

  • Common Name: Amoxi-Tabs®, Amoxi-Drops®, Robamox®
  • Drug Type: Beta-lactam antibiotic
  • Used For: Bacterial infections
  • Species: Dogs, Cats
  • Administered: Tablets, Oral liquid
  • How Dispensed: Prescription only
  • Available Forms: 50 mg, 100 mg, 125 mg, 150 mg, 200 mg, 250 mg, 400 mg, 500 mg, and 875 mg tablets
  • FDA Approved: Yes

General Description

Penicillin was the first antibiotic made available to humans during World War II. It was very effective against gram-positive bacteria, but didn’t last long and was susceptible to stomach acid so was wasted inside the body.

Amoxicillin is the new and improved version of penicillin that is able to last longer, resist stomach acid, and kill both gram-positive and gram-negative bacteria. It is often used to prevent and treat infections found in cuts and wounds, the mouth, the upper respiratory system, and the bladder. Amoxicillin also has better absorption than another predecessor, Ampicillin.

It is possible for bacteria to build resistance to this drug, as the Staphylococci group of bacteria already has. Amoxicillin may be used in conjunction with clavulanic acid (as in Clavamox) to be effective against Staphylococci as well as other bacteria.

This drug should be given for at least 7-10 days to be effective.

How It Works

Amoxicillin kills bacteria by preventing them from building a proper cell wall while they grow. It accomplishes this by inhibiting the linking of peptidoglycan chains that are a major component in both gram-positive and gram-negative bacteria’s cell walls.

Storage Information

Store tablets in a tightly sealed container at room temperature.

Keep oral liquid refrigerated- effective 14 days after mixed.

Injection is effective 3 months after reconstitution at room temperature and 1 year after reconstitution if refrigerated.

Missed Dose?

Give the dose as soon as possible. If it is almost time for the next dose, skip the missed dose, and continue with the regular schedule. Do not give your pet two doses at once.

Side Effects and Drug Reactions

Amoxicillin may result in these side effects:

  • Allergic reaction (labored breathing, hives, etc)
  • Loss of appetite
  • Drooling
  • Vomiting/Nausea
  • Diarrhea

Amoxicillin may react with these drugs:

  • Neomycin sulfate
  • Antacids
  • Aminoglycosides
  • Bacteriostatics (Drugs that inhibit bacterial growth)

DO NOT USE AMOXICILLIN IN RABBITS, GUINEA PIGS, OR RODENTS.


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