Visit our Christmas Shop
Black Friday Sale - Now on!

Logic Firm (previously Diar-Stop) for Dogs & Cats

  • Diar-Stop Cats & Dogs 2 - 7kg » 10ml Syringe £8.50
  • Diar-Stop Dogs 7 - 30kg » 24ml Syringe £9.49
  • Diar-Stop Dogs 30 - 60kg » 60ml Syringe £11.99
  • Diarsanyl Foals » 60ml Syringe £14.49

Selection of 4 products from

£8.50 to £14.49

Digestive upsets in dogs and cats occur when the intestines become irritated. This can be caused by a sudden change in diet or by eating inappropriate food, e.g. scavenging on a walk or eating from the rubbish bin.

Logic® Firm is a pharmaceutical grade formulation which helps support a dog or cat’s digestion.


  • Montmorillonite - Coats and protects the intestinal lining and absorbs toxins
  • Sodium, Magnesium & Potassium - Help to restore electrolytes lost through diarrhoea
  • Dextrose - Provides an energy source for the small intestine
  • Prebiotics (FOS – fructo-oligosaccharides) - Help to restore the normal bacterial flora



Fructo-oligosaccharides, Dextrose, Glycerol, Sodium chloride, Magnesium salts of organic acid.


Bentonite - montmorillonite (E558) 40%, Potassium sorbate.

Analytical constituents

  • Crude ash - 35%
  • Total sugars - 30%
  • Moisture - 22%
  • Sodium - 2.5%
  • Crude protein - 0%
  • Crude fibre - 0%
  • Crude oils & fats - 0%

Feeding guidelines

Pet Weight

Syringe Size
Syringe Size
Syringe Size
0 – 7 For Cats and Dogs
7 – 30 For Dogs only
> 30 For Dogs only
Body Weight Number of Graduations
Morning Evening
2kg - 7kg 1 1
8kg - 30kg 1 1
> 30kg 1 1

Need help or advice? Contact us:

  • Landline: 01582 842096
  • Mon - Fri: 8:30am - 5:30pm
  • Sat: 9:00am - 1:00pm
  • Email:

All prices include VAT where applicable.

Reviews of Logic Firm (previously Diar-Stop) for Dogs & Cats

Read our customers' reviews of Logic Firm (previously Diar-Stop) for Dogs & Cats

Questions & Answers for Logic Firm (previously Diar-Stop) for Dogs & Cats

Below are some recent questions we've received regarding Logic Firm (previously Diar-Stop) for Dogs & Cats, including answers from our team.

Ask Your Own Question

Suitable for kittens?

11th Oct 2017

I have two 14 week old kittens who have been suffering diarrhoea. Is this product suitable for them?

  • Veterinary Advisor

Yes you can give this product to kittens once they have been weaned from their mother. It is a good idea to reduce the amount of food they are getting and give several small meals a day. They will recover much better if their digestion is not overloaded. You should see your vet though if the diarrhoea lasts for some time or the kittens look unwell.