Small Pets Hamsters

Wet Tail in Hamsters

Causes, Treatment, and Prevention

Dwarf Hamster

Kerstin Waurick / Getty Images

Wet tail in hamsters is a form of diarrhea that is also called proliferative ileitis. Arguably the most commonly seen illness in hamsters, wet tail can be a serious and fatal condition if not treated promptly. Here's how to identify, treat, and prevent wet tail in hamsters.

What Is Wet Tail in Hamsters?

Wet tail is a term used to describe diarrhea or loose stools in hamsters due to an overgrowth of intestinal bacteria. It's also known as proliferative ileitis or regional enteritis. The phrase "wet tail" refers to just that—a wet tail on your pet hamster.

Symptoms of Wet Tail in Hamsters

Wet tail may cause several symptoms in hamsters. Watch for the following signs:

  • Wet tail and surrounding areas that may be matted with stool
  • Foul odor
  • Diarrhea or loose stools
  • Unkempt appearance from lack of grooming
  • Lethargy
  • Poor appetite
  • Hunched posture
  • Folded ears
  • Sunken eyes
  • Dehydration
  • Aggressive behavior

Once the signs of wet tail appear, your hamster is very sick and needs to see an exotic veterinarian as soon as possible.

What Causes Wet Tail in Hamsters?

Wet tail is caused by an overgrowth of bacteria in the gut. Most often, Lawsonia intracellularis is the culprit, but other types of bacteria can cause diarrhea in hamsters. Wet tail can affect hamsters of any breed or age, but it's most common in Syrian hamsters, baby hamsters, and older hamsters.

Several factors may cause the bacterial overgrowth that leads to wet tail in hamsters.

Stress

Stress is typically the main cause of wet tail. Baby hamsters can easily develop wet tail after weaning due to stress and dietary changes. Young hamsters get moved from a breeder or vendor to a pet store, to a new home, and sometimes get returned to the store after that, all within a period of a few weeks. This would stress anyone out—especially a tiny baby hamster. This stress causes the bacteria to overpopulate in the gut, which in turn causes diarrhea.

Unsanitary Conditions

A hamster that has spent time in a dirty environment is more prone to developing wet tail. This is likely die to a combination of stress and exposure to germs.

Exposure to Another Sick Hamster

Wet tail is also extremely contagious. If your new hamster was kept in a large cage with other hamsters that had wet tail, your hamster and/or the other hamsters could get it too. When picking out a hamster to take home, make sure it is active and running around to decrease the likelihood of it having wet tail already.

How Do Vets Diagnose Wet Tail in Hamsters?

An exotics veterinarian can examine your hamster and determine if the diarrhea is bacterial. Hamsters can have diarrhea for reasons other than wet tail disease. For example, a hamster may eat fresh fruit or veggies with high water content and suddenly develop diarrhea. This diarrhea is most likely not from wet tail, but from all the extra water content he took in. Be sure to discuss your hamster's history with your exotics vet to help them make an accurate diagnosis.

How to Treat Wet Tail

If your hamster has wet tail, your exotics veterinarian will likely prescribe antibiotics that are safe for hamsters and may also give subcutaneous fluids for rehydration. You might need to syringe feed a special hamster food (such as Oxbow Critical Care or Emeraid) or vegetable baby food if he is not eating.

If you are unable to take your hamster to an exotics vet right away, call and ask the vet about giving wet tail drops at home. These orange-flavored antibiotic drops can be purchased without seeing a veterinarian, but they're not as effective as prescription-strength antibiotics. The drops can be added to the water bottle or placed directly in the hamster's mouth. If your hamster does not improve on wet tail drops within one to two days, be sure to see a vet. Hamsters decline in health very quickly and time wasted could mean a fatal outcome for your hamster.

Prognosis for Wet Tail in Hamsters

Unfortunately. wet tail is often fatal, especially in very young or old hamsters. Early detection and treatment increase the odds of survival, so contact an exotics veterinarian as soon as you think your hamster is sick.

How to Prevent Wet Tail

You can't always prevent wet tail, but there are some steps you can take to reduce the chances of it happening to your hamster:

  • When choosing a hamster from a pet store, make sure it is active, that its eyes are open, and that its rear end is dry and free of fecal matter. To play it even safer, don't take home a hamster that is living with another hamster that doesn't look too healthy (i.e., eyes closed, sitting in the corner, wet bottom).
  • Some exotics veterinarians recommend treating your hamster with wet tail drops preventatively when you take home your new hamster. This can be done by mixing the appropriate amount of wet tail drops into your hamster's water bottle.
  • Clean your hamster's cage and toys regularly (at least weekly) to ensure they have a sanitary environment.
  • If you have more than one hamster and one comes down with wet tail, separate them immediately and be sure you wash your hands after handling the sick one and before handling the healthy one.
  • Bring new hamsters to an exotics vet for a wellness examination within the first month of bringing them home. This can help find signs of dehydration, diarrhea, and any other concerns you may have for your new pet. This is also a great time to discuss any other concerns you may have for your new pet.
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  2. HamstersMerck Veterinary Manual.