Two Easy Ways to Start Earning Rewards!
Become a member today!
Members-only pricing and offers, personalized care notifications, Vital Care points back on every purchase and more!
Already a member? Sign in
Become a credit card member today!
Earn 2X Pals Rewards points at Petco
when you use Petco Pay!
APPLY NOW
Learn More About Petco Pay Benefits

My cat has bloody diarrhea after antibiotics. Is it from irritation?

Updated on September 23rd, 2025

Pet's info: Cat | Domestic Shorthair | Male | neutered | 1 year and 2 months old | 11 lbs

Hi, My cat was on antibiotics for 2 weeks because of a cat flu. He started to have diarrhea a few days ago just right before his antibiotic course was coming to an end. 2 days ago his course was done and the diarrhea still there but now with a little bit of fresh blood. I know now that antibiotics can cause diarrhea but the diarrhea that present for a few days could cause bleeding because of the irritation ? Otherwise my cat is healty, never had diarrhoea or any other healthy issues.

4 Answers

Most Helpful Answer

Answered By Susan England-Foster

Veterinarian

Published on July 14th, 2017

It is very possible the blood is from the irritated colon. The colon gets irritated secondary to the diarrhea. You can try an over the counter probiotic to help good bacteria return to the colon and help stop the diarrhea. If the diarrhea does not resolve he needs to see a vet for possible stronger medications.

2Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Jenna Beyer, DVM, MBA, cVMA
Veterinarian, Certified Veterinary Acupuncturist
Published on June 11th, 2019
The progression of the diarrhea from yesterday to today appears to be a little better (it looks like there is a lot of blood in the stool in the first picture). I would continue with your vet's treatment plan.
1Pet Parents found this answer helpful
Answered By Dr. Melanie, BVSc MS
Veterinarian
Published on February 23rd, 2019
Thank you for contacting Petco Pet Education Center, formerly Petcoach with your question about George. I’m sorry he isn’t doing well. Antibiotics can cause GI upset such as diarrhea, but I would be concerned about the blood as that isn’t a typical side effect of them. When dogs have diarrhea, their bowels become irritated and you can see some blood. I’d watch him for now, and if the bloody stools continue, then I would take him into the vet. I hope this helps!
1Pet Parents found this answer helpful
Answered By Destini R. Holloway, DVM
Veterinarian
Published on July 23rd, 2017
When two antibiotic are used there can be a reduction in some of the food bacteria in the gut. I would recommend giving Ralph daily probiotics such as over the counter Culturelle to help her the bacterial flora back balanced. If he is still having blood after 24-48 hrs then it's best to have him seen by your vet for further care. Best wishes and take care.
1Pet Parents found this answer helpful

Smart Picks for Smart Questions

Related Questions

Health & Wellness

My 6-month-old cat has recurring bloody diarrhea. What should I do?

Thank you for contacting Petco Pet Education Center, formerly Petcoach with your question. Poor kitty! It's time to see the vet again since her poo is bad again with blood in it. She may have have something like coccidia or Giardia causing this issue, and those can take a while to treat. I'd take her back to the vet in the morning. Best of luck.

Updated on September 23rd, 2025

Health & Wellness

Why does my 2-month kitten have bloody, mucousy diarrhea after shots?

This can commonly occur after intestinal parasites or stress from vaccinations. Your cat most likely need some antibiotics and possibly a probiotic to help get the gut health back to where it needs to be. Once this occurs the diarrhea should resolve. I hope this helps. Thanks for using Petco Pet Education Center, formerly Petcoach. Best of luck.

Updated on September 23rd, 2025

Food & Nutrition

Why does my cat still have liquid diarrhea after antibiotics?

Alfie could have a parasite, infection, inflammatory bowel disease, hyperthyroidism, liver/kidney disease, etc. Since it has been a week, it would be a good idea to have full blood work, fecal test, and x-rays done to rule out potential causes. I would also recommend switching to a hypoallergenic diet, like d/d, and see if that helps. A medication called Proviable KP may also help. If your vet didn't already prescribe Metronidazole (Flagyl) than that could be tried, too. If the diarrhea persists than an intestinal biopsy may be needed.

Updated on September 23rd, 2025

My cat has diarrhea after antibiotics. Should I take him to the vet?

I would recommend seeing the vet. At this point even if the diarrhea was initially related to the antibiotics Jasper may now have a disruption of his normal intestinal flora that requires additional treatment. It's also possible that the diarrhea is unrelated to the antibiotics and instead is due to intestinal parasites or a food sensitivity. If you wait until he stops eating or loses weight he may require more intensive treatment so I'd recommend making an appointment to see your veterinarian this week.

Updated on September 23rd, 2025

Why is my cat's rectum red with pus and bloody diarrhea?

With so many symptoms I recommend a vet check as soon as possible - it sounds like he has developed a severe diarrhea/colitis and fecal incontinence and he requires urgent treatment. In the meantime offer a bland diet of boiled chicken or fish and a probiotic supplement such as fortiflora

Updated on September 23rd, 2025

Health & Wellness

Is it normal for my cat to poop blood after a vet visit for diarrhea?

Thank you for contacting Petco Pet Education Center, formerly Petcoach with your question about Simba. Unfortunately there is no picture attached to your post, so I can't see what his poop looks like. Cats can easily get stressed, and that can lead to colitis. Colitis is inflammation of the colon, and that can cause blood in the stool. I'd keep an eye on him and his poop for now. If it continues to be bloody, give his vet a call. As for what happened with the vet, I suspect they may have used a cotton swab to get a sample of poop from his anus. I hope this helps!

Updated on September 23rd, 2025

Food & Nutrition

My cat has bloody diarrhea from stress and diet changes. Vet or home?

I'm sorry to hear that Casper has had so much diarrhea lately! Yes, it is certainly possible that the stress of his visitor coupled with his ingestion of the other cat's food and treats could have caused some gastroenteritis (inflammation in the gastrointestinal tract), which led to diarrhea. A bit of blood can occur in the stool as a result of irritation to the colon. If Casper is still eating, drinking and acting relatively normally, you can try a home remedy. Start by withholding food for 24 hours, then offer a bland diet of boiled white meat chicken for a few days before gradually mixing his normal food with the boiled chicken over another 5-7 days. If at any point Casper becomes lethargic, starts vomiting, has profuse bloody diarrhea, or stops eating, he will need to take a trip to the vet for further evaluation. I hope this helps and that all goes well!

Updated on September 23rd, 2025

Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Share