miralax for dogs and cats

Polyethylene Glycol 3350 (MiraLAX®) for Dogs and Cats

Overview of Polyethylene Glycol 3350 (MiraLAX®) for Canines and Felines

Polyethylene glycol 3350, commonly known as MiraLAX®, is used as a laxative to treat constipation for dogs and cats. It is also used to empty the intestines prior to diagnostic procedures. It is commonly used in humans before diagnostic procedures, such as a colonoscopy.
Polyethylene glycol 3350 belongs to the class of drugs known as osmotic laxatives. It works by creating an environment where water is retained in the stool. There are versions of Polyethylene glycol that contain electrolytes used primarily for preparation for colonoscopy in humans, like the product “Golytely®”.
The recommendations in this article are for the Polyethylene Glycol 3350 Powder, which is available in either pre-measured 17-gram packets or bulk powder such as MiraLax®, Dulcolax Balance®, and various generic names.
Polyethylene glycol 3350 is available without a prescription but should not be administered unless under the supervision and guidance of a veterinarian. Some pets will appear to strain, which can look like constipation but is a sign of a urinary obstruction or colitis.
This drug is not approved for use in animals by the Food and Drug Administration, but it is prescribed legally by veterinarians as an extra-label drug.

Human formulations: There are several different trade name products for docusate. Common names include Clearlax, Colyte, Dulcolax, Easylax, EZ2GO, Gavilax, Gavilyte, Gialax, Glycolax, Golytely, Healthylax, Laxaclear, Miralax, Moviprep, Natura-Lax, Nulytely, Pegylax, Powderlax, Purelax, Smooth lax, and Trilyte.
Veterinary formulations: None

Polyethylene glycol 3350 is used to stimulate bowel movements in animals with constipation or when there is a need to empty the large intestine, such as before a diagnostic procedure to examine the intestine.

Polyethylene glycol 3350 should not be used in animals with known hypersensitivity or allergy to the drug.
While generally safe and effective when prescribed by a veterinarian, Polyethylene glycol 3350 can cause side effects in some animals, including lethargy, nausea, vomiting, and/or increased thirst. Longer-term use can cause electrolyte imbalances, including high potassium and/or low sodium and dehydration.
Polyethylene glycol 3350 should not be used in animals with gastrointestinal obstructions, rectal bleeding, a tear in the intestinal wall (bowel perforation), or toxic colitis. It is also not approved for breeding, nursing, or lactating dogs or cats but is considered safe by many veterinarians.
Polyethylene glycol 3350 may interact with other medications. Consult with your veterinarian to determine if other drugs your pet is receiving could interact with Polyethylene glycol 3350. Such drugs include certain other laxatives and stool softeners.

Polyethylene Glycol 3350 Powder is available in either pre-measured 17-gram packets or bulk powder such as MiraLax®, Dulcolax Balance®, and various generic products.
Polyethylene glycol 3350 is available in various solutions that have added electrolytes, primarily used in humans as preparation for colonoscopy diagnostic procedures. Products include CL® Solution; CoLyte®; GoLYTELY®; NuLytely®, TriLyte®, and MoviPrep®.

Medication should never be administered without first consulting your veterinarian. If you're concerned about costs related to medication, pet insurance may be able to help. Click here to learn more.
Miralax dosage for dogs: The dose of Polyethylene Glycol 3350 Powder for solution varies with the size of the dog:
- Small dogs – 1/8 to ¼ teaspoon every 12 hours (twice daily)
- Medium sized dogs – ¼ to ½ teaspoon every 12 hours (twice daily)
- Large dogs – ½ to ¾ teaspoon every 12 hours (twice daily)
Miralax dosage for cats: The dose of Polyethylene Glycol 3350 Powder most used in a laxative is 1/8 to ¼ teaspoon every 12 hours on food.
The duration of administration depends on the condition being treated, response to the medication, and the development of any adverse effects. Be certain to complete the prescription unless specifically directed by your veterinarian. Even if your pet feels better, the entire treatment plan should be completed to prevent relapse.

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