POM-V Prescription Required Companion Animal

Laxatract 667 mg/ml Syrup for Dogs and Cats

Active ingredient: Lactulose

Form

Syrup

Species

Cats Dogs

Manufacturer

Dechra Regulatory B.V.

VMD MA No.

50406/4000

What it's used for

For the treatment of constipation (e.g. due to intestinal atony after surgery, hairballs, massive intestinal contents). For the symptomatic treatment of di...

Full indications, dosage and side effects ↓

View official SPC (PDF)

The prescription itself has a price. See what practices near you charge for a consultation and the written prescription fee.

Paying less for Lactulose

1

Ask your vet for a written prescription

They must provide one on request. Under the CMA Order the fee is capped at £21 from 2027.
2

Fill it at a registered online retailer

The CMA found online pharmacies 50–60% cheaper than practice dispensing on common medicines — typically £200–£300 a year.

Your prescription rights → VMD register of retailers →

Prescription required

Your vet must provide a written prescription on request. You can then purchase from any licensed online retailer.

Clinical information

Laxatract 667 mg/ml Syrup for Dogs and Cats — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 26 Mar 2026.

For the treatment of constipation (e.g. due to intestinal atony after surgery, hairballs,
massive intestinal contents).
For the symptomatic treatment of disease conditions which require facilitated
defecation (e.g. partial obstructions due to for example tumours and fractures, rectal
diverticulum, proctitis and poisoning).

For oral administration
Dogs and cats: 400 mg lactulose per kg bodyweight per day, corresponding to 0.6 ml
veterinary medicinal product per kg body weight per day. This should preferably be
divided into 2-3 doses over the day. The dosage may be adjusted as needed.
Approximately 2-3 days of treatment may be necessary before a treatment effect
occurs.

Issued: May 2019
AN: 01575/2017
Contact a veterinarian to adjust the treatment if abdominal discomfort or diarrhoea
occur. The veterinary medicinal product can be mixed with feed or given directly into
the mouth.

Do not use in animals with total gastro-intestinal obstruction, digestive perforation or
risk of digestive perforation.
Do not use in cases of hypersensitivity to the active substance or to the excipient.

Signs of flatulence, gastric distention, cramping, etc. are common early in therapy,
but generally abate with time. Diarrhoea and dehydration are signs of (relative)
overdose; if this occurs, a veterinarian should be consulted.
The frequency of adverse reactions is defined using the following convention:
- very common (more than 1 in 10 animals treated displaying adverse reaction(s))
- common (more than 1 but less than 10 animals in 100 animals treated)
- uncommon (more than 1 but less than 10 animals in 1,000 animals treated)
- rare (more than 1 but less than 10 animals in 10,000 animals treated)
- very rare (less than 1 animal in 10,000 animals treated, including isolated reports).

None.

Issued: May 2019
AN: 01575/2017

Special precautions for use in animals
Lactulose solution contains some free lactose and galactose, and may alter the
insulin requirements in diabetic patients. Use with caution in animals with pre-existing
fluid and electrolyte imbalances, since lactulose may exacerbate these conditions, if
diarrhoea occurs.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals
This veterinary medicinal product may cause flatulence and diarrhoea. Accidental
ingestion should be avoided, especially by a child. To avoid accidental ingestion, the
veterinary medicinal product must be used and kept out of reach of children. Always
replace the cap after use.
This veterinary medicinal product contains benzyl alcohol. This preservative may
cause hypersensitivity (allergic) reactions. People with known hypersensitivity to
benzyl alcohol should avoid contact with the veterinary medicinal product. Wash
hands after use. In case direct contact with skin or eyes should occur, rinse with
clean water. If irritation persists, seek medical advice.

None known.

This veterinary medicinal product does not require any special storage conditions.

Not applicable
5.

This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.