My old Chihuahua's poop is black and bloody. What's going on?

This is very concerning and indicates internal bleeding and ulceration and possibly an intussuception where the gut has folded in on itself. She needs emergency veterinary care immediately and at such an age such a severe presentation could become life-threatening

It sounds as Peanut is suffering from a gastrointestinal condition, possibly an infection. it could also be due to ingestion of a foreign body material. i would recommend taking him to the vet the first chance you get, he will need to be checked first, if the vet thinks it's a simple gastrointestinal infection he will need an anti nausea injection, antibiotics and a special food for a few days in order to get better.

Hello. At this age I would be concerned about cancer, but it may also be an infection in one of her anal glands, a parasitic infection, or colitis. It is best to see your vet about this as soon as possible so that little Perla does not have more problems. thanks for using Petco Pet Education Center, formerly Petcoach.

Oh no, Chaquita! There can be several conditions that cause pure blood in the stool (referred to as hematochezia), and these include hemorrhage gastroenteritis (HGE), a bleeding ulcer, cancer, parvovirus, a clotting disorder (from rat poison ingestion or genetic), among others. Regardless of the cause, this is a very concerning sign because it can rapidly lead to blood loss and dehydration. Chaquita needs to be taken to an ER vet immediately for an exam, lab testing (CBC, chemistry, coagulation panel), and supportive care (IV fluids, etc.).

Good that the full workup last week was normal. Isabella may be straining to pass hard stool, and I'd recommend adding a bit of fiber like pumpkin to her diet, or ask your vet for a stool softener. She may be straining so hard that she is causing bleeding in her little anus area, or her anal glands could have some bloody discharge. If she is eating and drinking and not acting painful this is a good sign that nothing major is going on. I like Royal Canin Fiber diet for these issues as a long-term diet.

Poor Mimi  The hives and itchy patches can be caused by an allergic reaction, and antibiotics can cause vomiting as a side effect. What I'm concerned about is the black poop, which indicates bleeding from the upper GI tract. She sounds very sick, and you cannot treat this at home. Please take her into a vet immediately.

Based on what you seeing, having a fecal sample brought in to your veterinarian for analysis would be a great plan. He or she will be able to tell you if there are any intestinal parasites present. This is one of the most common reasons for blood in the stool, and weight loss despite a normal appetite. If you can not get to the veterinarian, treatment with a dewormer and/or drug to kill coccidia might be warranted. These can be obtained at most pet stores or tractor supply.