Tomlyn Firm Fast Medication for Digestive Issues & Diarrhea for Cats & Dogs, 15-cc syringe

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At a Glance

  • Digestive Health
  • All Lifestages
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About This Item

Details

  • Formulated to reduce the amount of water in loose stools.
  • The probiotic supports your pet’s immune system while displacing bad bacteria.
  • A great homeopathic medicine to use after loose stools are seen or before stressful events that can lead to loose stools like traveling and boarding.
  • Paw-fect for canine companions and feline friends.
  • The syringe option has a tasty chicken flavor and the tablets have an irresistible beef liver flavor.

Ingredient Information

Feeding Instructions

Frequently bought together

Questions & Answers

7 Customer Questions

How much do I feed this to a cat?

Answer by Chewy • Feb 20, 2020
For cats 10 pounds and under, the manufacturer recommends giving 1 cc every 8 hours. Cats 11 pounds and up should get 1 additional cc (dose of 2 cc's) of gel every 8 hours.

Can you give this to a nursing cat?

Answer by Chewy • May 22, 2023
At this time, there are no safety studies on pregnant or nursing mothers using this product. It is formulated to be a very safe product. There are no known contraindications for using the product.

What is the shelf life of this product?

Answer by Chewy • Sep 08, 2021
This supplement has a shelf life of 3 years from the manufacture date.

Can I use this long term?

Answer by Chewy • Oct 02, 2025
This is designed as a short-term remedy for loose stools in pets and is not intended for long-term use.
Reviews
Write a Review
4.2
Rated 4.2 out of 5 stars
100 Ratings
Terms & Conditions

Customers Mention

Chewy identifies key considerations with the help of artificial intelligence and our veterinarians.

Ease of Use

81% Positive

Effectiveness

79% Positive

Ingredients

64% Positive

Speed of Relief

72% Positive

38 Customer Reviews

Always consult a veterinarian about your pet’s health needs. Customer reviews should not be used as medical advice.

Rated 5 out of 5 stars
By Margeaux on Dec 4, 2025

vet like kaopectate

usually give, if absolutely needed, Kaopectate, for humans. saw this and I really like Tomlyn products, so I tried it. seems to work as good as human grade and

usually give, if absolutely needed, Kaopectate, for humans. saw this and I really like Tomlyn products, so I tried it. seems to work as good as human grade and I am sure safer for my girl. used half- dose.

Rated 5 out of 5 stars
By Laura on Aug 13, 2025

Easy to use

It works quickly to stop situational diarrhea. In my dog's case, she had been given Carprophen for pain after her spaying. When I picked her up, she had liquid mustard

It works quickly to stop situational diarrhea. In my dog's case, she had been given Carprophen for pain after her spaying. When I picked her up, she had liquid mustard stool. That night, it was bloody, which Carprophen can cause. So no more of that, and my dog seemed pain free anyway. No food for 24 hours, white rice served in a lot of water, and dosages of Firm Fast as listed. It took about a week to get a pretty normal stool.

Rated 5 out of 5 stars
By Heather on Nov 17, 2025

This stuff works!!

I have used this product on all of my dogs and yes it works in minutes. Amazing stuff and I always keep some on hand.

I have used this product on all of my dogs and yes it works in minutes. Amazing stuff and I always keep some on hand.

Rated 2 out of 5 stars
By Candace on Oct 24, 2025

Slow acting stool medicine

This has only decreased the number of loose stools after 4 days of use. I do not recommend.

This has only decreased the number of loose stools after 4 days of use. I do not recommend.

Rated 5 out of 5 stars
By ray on May 2, 2025

This was a godsend

This was very well needed in the last quarter of my dog’s life, throughout his entire life. He never had any issues but the last third of his life which he lived

This was very well needed in the last quarter of my dog’s life, throughout his entire life. He never had any issues but the last third of his life which he lived to be almost 18, he went through bouts of diarrhea, one dose of this and it stopped it immediately.

Rated 5 out of 5 stars
By Kate on Jul 7, 2025

It works quickly and gently.

And, my dog likes the flavor. As we all know, your dog's desire to take the medicine is a big deal.

And, my dog likes the flavor. As we all know, your dog's desire to take the medicine is a big deal.

Rated 5 out of 5 stars
By BJ on Apr 23, 2025

Firm fast

Used for our young cat. She developed diarrhea after surgery that did not resolve on it's own. After 2 doses of firm fast the diarrhea cleared up and she began eating

Used for our young cat. She developed diarrhea after surgery that did not resolve on it's own. After 2 doses of firm fast the diarrhea cleared up and she began eating and drinking. I highly recommend this product.

Rated 5 out of 5 stars
By Anthony on Jul 1, 2025

Super fast service

Jeeeezzzz, Chewy is no joke doing business. They deliver super fast with good prices, Thanks

Jeeeezzzz, Chewy is no joke doing business. They deliver super fast with good prices, Thanks

Rated 5 out of 5 stars
By Courtney on Apr 24, 2025

Great product

My sweet pup has been on antibiotics for a couple of weeks and as a result has some diarrhea issues - this helped so much! I highly recommend!

My sweet pup has been on antibiotics for a couple of weeks and as a result has some diarrhea issues - this helped so much! I highly recommend!

Rated 1 out of 5 stars
By Kristy on Aug 18, 2025

Dont waste your money

It doesn't work makes it worse

It doesn't work makes it worse