Lactulose
Also known as: Cephulac, Constulose, Enulose, Kristalose, Generiac, Duphalac, Lactugal, Laevolac
### What to Expect * **The Goal**: The ideal outcome of lactulose therapy is **2 to 3 soft, semi-formed stools per day** (think of the consistency of soft-serve ice cream). * **Adjustments**: Your veterinarian will likely have you adjust the dose slightly up or down based on your pet's stool consistency. ### Important Warnings * **Watch for Diarrhea**: If your pet develops watery diarrhea, stop the medication and contact your veterinarian immediately, as this can lead to dangerous dehydration. * **Liver Disease**: If your pet is taking this for liver disease (hepatic encephalopathy) and their neurological signs worsen (e.g., stumbling, staring into space, head pressing) or they are having fewer than 2 soft stools a day, contact your vet right away. ### Tips for Cats * Cats often hate the sticky, sweet taste of the liquid syrup and may drool excessively or run away. * If you are struggling to give the liquid, ask your veterinarian about **lactulose crystals** (*Kristalose*), which can be easily mixed into canned food and are usually much better accepted.
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- Hepatic encephalopathy
- Constipation
- Constipation
- Constipation
- Chronic constipation (maintaining soft stools)
- Hepatic encephalopathy / Constipation
- Hepatic encephalopathy; to stimulate appetite, improve intestinal flora
- Laxative
- Hepatic encephalopathy
- Hepatic encephalopathy
- Hepatic encephalopathy crisis
- Hepatic encephalopathy
- Hepatic encephalopathy
- Constipation
How it is given
Possible side effects
- Flatulence
- Gastric distention
- Abdominal cramping
- Diarrhea (dose-dependent)
- Dehydration (secondary to excessive diarrhea)
- Hypersalivation/aversion in cats (due to taste/texture)
- Diarrhoea
- Dehydration (with excessive dosing)
Cautions & contraindications
- Patients requiring a low-galactose diet
- Use with caution in diabetic patients (contains free lactose and galactose)
- Use with caution in patients with preexisting fluid and electrolyte imbalances
- Severely encephalopathic animals at risk of inhalation/aspiration
- Gastrointestinal obstruction
- Animals at risk of gastrointestinal perforation
- > **Diabetic Patients**: Lactulose syrup contains some free lactose and galactose, which may alter insulin requirements. > **Electrolyte Imbalances**: Lactulose-induced diarrhea can exacerbate preexisting fluid and electrolyte imbalances. Monitor hydration and serum electrolytes during long-term therapy. > **Feline Administration**: The syrup is notoriously difficult to administer to cats due to taste aversion; consider using lactulose crystals mixed with food.
Drug interactions
- Oral Antacids: Non-adsorbable antacids may reduce the colonic acidification effects and overall efficacy of lactulose.
- Other Laxatives: Should not be used concurrently; loose stools may be falsely attributed to lactulose, resulting in inadequate dosing for hepatic encephalopathy.
- Neomycin (and other oral antibiotics): Theoretically, oral antibiotics could eliminate the colonic bacteria required to metabolize lactulose, reducing its efficacy. However, clinical synergy is often observed when treating hepatic encephalopathy. Enhanced monitoring is recommended.
- Oral antibiotics (e.g., neomycin): Synergy may occur when used together for hepatic encephalopathy.
- Insulin: Lactulose syrup contains free lactose and galactose, which may alter insulin requirements in diabetic patients.
- 5-aminosalicylic acid (and other pH-dependent colon-release drugs): Can be inactivated because lactulose decreases the pH of the colon.
Frequently asked questions
What is Lactulose used for in pets?
### What to Expect * **The Goal**: The ideal outcome of lactulose therapy is **2 to 3 soft, semi-formed stools per day** (think of the consistency of soft-serve ice cream). * **Adjustments**: Your veterinarian will likely have you adjust the dose slightly up or down based on your pet's stool consistency. ### Important Warnings * **Watch for Diarrhea**: If your pet develops watery diarrhea, stop the medication and contact your veterinarian immediately, as this can lead to dangerous dehydration. * **Liver Disease**: If your pet is taking this for liver disease (hepatic encephalopathy) and their neurological signs worsen (e.g., stumbling, staring into space, head pressing) or they are having fewer than 2 soft stools a day, contact your vet right away. ### Tips for Cats * Cats often hate the sticky, sweet taste of the liquid syrup and may drool excessively or run away. * If you are struggling to give the liquid, ask your veterinarian about **lactulose crystals** (*Kristalose*), which can be easily mixed into canned food and are usually much better accepted.
Is Lactulose safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
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