(Chronulac® and Cephulac® are other names for this medication.)

Use: Lactulose is a medication that is used as a stool softener to treat constipation. Some cats with a condition called megacolon (flaccid intestines causing constipation) may need to receive lactulose for most of their lives. It can also be used in liver disease to help reduce ammonia that can build up in the blood.

Side Effects: Diarrhea is the most common side effect of lactulose. You should make sure your animal has plenty of clean water to drink while being treated with lactulose to prevent dehydration.  Some animals will become gassy and experience stomach cramping.

Precautions: Lactulose is comprised of sugars and may cause problems in diabetic animals. You may need to alter your pet’s insulin dose when administering lactulose. Talk to your veterinarian if your pet is diabetic.

Directions: Dogs and cats usually receive lactulose orally 2-4 times daily. Lactulose is usually given orally up to three times daily. It is a sticky, sweet oral liquid that may be difficult to get into cats. To treat constipation, it should be given until the pet produces 2-3 very soft stools daily.

Remember: Lactulose should be stored in a tight, light resistant, childproof container away from all children and other household pets. Refrigeration is not required and may make the drug too thick to remove from the medication container.

If you miss a dose of this medication you should give it as soon as you remember it, but if it is within a few hours of the regularly scheduled dose, wait and give it at the regular time. Do not double a dose as this can be toxic to your pet.