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Drug Details

  • Drug Name: Lactulose
  • Common Name: Enulose®
  • Drug Type: Laxative
  • Used For: Constipation, Liver disease
  • Species: Dogs, Cats
  • Administered: Oral liquid
  • How Dispensed: Prescription only
  • FDA Approved: No

General Description


Lactulose is a synthetic sugar that combines fructose and galactose. It is typically used as a laxative. It is sometimes used for pets with liver disease and enlarged livers (hepatic encephalopathy), though there is some controversy on it’s effectiveness in treating these disorders.


How It Works


When your pet takes lactulose, the syrup travels through their digestive tract without being absorbed. There, bacteria can break it down which makes the intestines more acidic. The acidity draws water into the intestine, loosening the stool. These acids also convert toxic ammonia in the colon into ammonium, which is then passed in the stool.


Storage Information


Keep in a tightly sealed container at room temperature protected from light. Do not refrigerate.


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


Lactulose may result in these side effects:

  • Bloated belly
  • Abdominal pain
  • Gas
  • Diarrhea
  • Dehydration


Lactulose may react with these drugs:

  • Antacids
  • Antibiotics
  • Other laxatives


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