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what does it mean when a hamster is bleeding from its bum?

Why Is My Hamster’s Bum Bleeding?

(Last Updated On: May 28, 2022)

Part of caring for a hamster involves managing its health needs. While hamsters are comparatively robust animals, they can grow unwell. If your hamster is bleeding from the bottom, something is amiss.

If a hamster bleeds from its bum, it may have wet tail (watery diarrhea) or pyometra (uterine infection). Also, it could have rectal prolapse due to gastrointestinal issues or be bleeding due to a UTI.

Some hamsters bleed from the bottom because they scratched themselves. Ensure your hamster enjoys a regular digestive cycle and empties its bowels without any issues.

What Does it Mean When a Hamster is Bleeding from its Bum?

If you notice blood in your hamster cage, lift your hamster and check its rear end.

If you discover this is the source of the bleeding, consider why this may be the case. It could be as simple as your hamster scratching itself or something more concerning.

Hamsters have sharp claws and fastidiously groom themselves. Your hamster may have accidentally clipped the soft, delicate skin of its anus during this process. Alternatively, your hamster may have experienced an impact trauma.

Assuming that your hamster isn’t bleeding after an accident, such as falling from the top of its cage while climbing or monkey barring, there are six core explanations for rectal bleeding:

Blood in the Urine

If you find spots of blood in a hamster’s bed, it may be due to a urinary tract infection (UTI) or a problem with the internal organs. This can cause a hamster to tear its uterine lining, leading to blood leaking from the anus.

UTIs are quite common in hamsters as they urinate and defecate in their substrate. Regular spot cleaning will reduce the risk of a hamster UTI, but bacteria can still enter the urethra. If the hamster is infected, it will pass blood in the urine.

Hamsters with a UTI will be in pain and may behave erratically. The hamster may try to pass the infection by drinking more water, so look out for warning signs of polydipsia (hydrating beyond the point of thirst) and polyuria (passing excessive urine.)

If a UTI is left untreated, it’ll likely evolve into kidney disease. Seminars in Avian and Exotic Pet Medicine warn that renal failure is comparatively common in senior hamsters but can be managed with early detection and treatment.

Take your hamster to a vet if you suspect bleeding from the anus is related to a urinary infection, especially if it’s also losing weight. Oral antibiotics will resolve the concern. Enrofloxacin will usually be prescribed under the brand name Baytril.   

Gastrointestinal Issues

If your hamster struggles to pass fecal matter, it could experience a prolapsed rectum.

In some cases, the hamster will continue to behave as normal; drinking water, exercising, and eating. However, a prominent part of the hamster’s bowel and rectum will protrude outside the body.

A prolapsed rectum may begin with diarrhea, which will leave the hamster straining to empty its bowels. A common cause of diarrhea is excessive consumption of fresh fruit and vegetables.

If a hamster is dehydrated, the opposite may arise. Stools will be too hard to pass easily, and the hamster will bleed from the rear as it eliminates. If this happens enough, the rectum will prolapse under the strain.

Another gastrointestinal concern that could explain anal bleeding in hamsters is intussusception. This condition arises when the intestines fold into each other, causing a blockage and intense abdominal pain.

This condition can only be resolved with surgery.

what to do if your hamster’s bum is bleeding

Wet Tail (Proliferative ileitis)

Wet tail (proliferative ileitis) is a bacterial infection that impacts hamsters. Younger Syrian hamsters are most susceptible to wet tail. Unless the condition is treated urgently, it is frequently fatal.

Wet tail manifests as diarrhea, hence the name of the condition. Your hamster will have messy, watery fur around the anus. As discussed, this diarrhea can lead to rectal prolapse and anal bleeding.

Other symptoms of wet tail include weight loss, lethargy, dehydration, and sunken eyes.

At the first signs of wet tail, seek veterinary advice, as this condition will often be fatal within 48 hours. A vet will prescribe the antibiotic chlortetracycline as treatment.


So far, our potential explanations for rectal bleeding in hamsters have been gender-neutral.

If you’re asking, “why is my male hamster bleeding from its bottom?” you can skip this section. Pyometra is a condition that only applies to female hamsters.

Pyometra is most frequently found in senior hamsters, especially those that have mated multiple times and produced several litters of pups.

Pyometra is caused by pus building within the uterus, often due to excess bacteria. This pus results in a discharge of blood.

There are two types of pyometra, dubbed open and closed.

Veterinary Quarterly explains that in the case of open pyometra, a foul-smelling white discharge accompanies bleeding. This form of pyometra is easier to spot and treat. A vet will drain the infection.

Closed pyometra unfolds inside the hamster’s body, making it hard to spot symptoms. This means that close pyometra is often fatal. As symptoms aren’t recognized until the latter stages, the bacteria can spread throughout the hamster’s body and cause sepsis. 

Other warning signs are a distended, swollen belly, excessive thirst, and lethargy.

Cancerous Tumors

Hamsters are prone to tumors. If you’re stroking a hamster, you may discover new lumps and bumps on the skin. This doesn’t always mean that the node is dangerous.

Hamster tumors come in three forms:

  • Benign tumors are non-cancerous.
  • Pre-malignant tumors start off benign but increase in risk as the hamster ages.
  • Malignant tumors are cancerous and likely to be fatal.

Aside from a physical lump on your hamster’s skin, the symptoms of a cancerous tumor include lethargy, excessive thirst, and hair loss. Anal bleeding can be the final warning sign.


Unless you’re actively breeding hamsters, your hamster is unlikely to be pregnant.

If a hamster is carrying pups, she may start spotting and bleeding. This can look like bleeding from the anus at first glance. Equally, as with UTIs, the uterine lining may be torn.

Female hamsters are fertile at six weeks of age, with males becoming sexually active at four weeks. Ordinarily, a licensed breeder or pet store will separate hamsters into solo habitats or single-sex groups by this age. However, mistakes sometimes happen.

Hamsters only gestate for around three weeks – even less in the case of a Syrian. Pregnancy can only explain bleeding for a short amount of time.

A hamster bleeding from the bottom is always serious, but it doesn’t need to be terminal. If you find blood around a hamster’s bottom, a veterinarian should examine it.