Why Does My Hamster Have a Lump?

Hamsters are small rodents that make excellent house pets. They’re popular for their size and appearance and are relatively low-maintenance. However, hamsters may encounter certain health issues in their 2 to 4 years life span, such as a lump. If you notice a lump on your hamster’s body, you surely want to know if it’s something to worry about.

Your hamster has a lump, likely because of sickness—the lump results from infections or tumors, which can either be benign or malignant. You can’t determine whether your hamster has an abscess or a tumor by simply eyeballing and palpating. Take your hamster to the vet as soon as you can.

A licensed veterinarian will have to perform a needle aspirate biopsy and submit it for pathology to determine the nature of the lump. Keep reading to learn more about it.

An Infection Will Cause Abscess in Hamsters

Abscesses are masses on the skin resulting from localized pus buildup as part of the body’s response to infection. While this is a natural process to combat infection, the abscess may cause discomfort or distress. Common causes of infection in hamsters are discussed below:

Why Does My Hamster Have a Lump
Why Does My Hamster Have a Lump

Your Hamster May Have Bitten Itself or Injured by Other Hamsters

Abscesses, specifically in hamsters, may start as a cut that becomes a portal for infection. In many cases, the wound is self-inflicted as hamsters might inadvertently bite themselves in the course of grooming.

The bites could also result from rough play with other hamsters. Hamsters that live in pairs or groups may break out into fights that conclude with bite wounds on the bodies of one or more of those involved.

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Your Hamster’s Habitat May Not Be Safe

Hamsters may sustain injuries due to the design of their living area. In isolation, they may get cuts or scratches from items in their cages. Toys and decorative items might sometimes have sharp edges.

That said, make sure your hamster cage is as safe as possible for your hamster. Make sure to check your hamster from time to time to ensure that it’s free from injuries. If your hamster has any injury, especially a severe one, you should take it to the vet right away.

Sharp Objects May Have Hurt Your Hamster’s Cheek Pouches

Hamsters are eager eaters. Abscesses may also form when sharp objects get stuck in or scratch the inside of a hamster’s cheek pouches, which can occur during eating. Left unnoticed and untreated, these breaks in the skin allow bacteria into the body, and infection follows.

Take Your Hamster to the Vet for an Abscess Diagnosis

Visit your local veterinarian if you observe a lump growing on your hamster’s body or suspect that they may have one in their cheek pouches. Your hamster might otherwise seem fine, but a visit to the vet to rule out something serious is always a good idea.

If an abscess ruptures, it’ll be telling of what the lump actually was. But by and large, the nature of a lump can only be established through proper assessment and procedures. It’s usually achieved by determining its contents by performing a needle aspirate biopsy.

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How To Treat Abscesses in Hamsters

Treatment can range from an antibiotic prescription to a more invasive procedure known as incision and drainage. The earlier treatment is sought, the less aggressive the treatment may need to be.

Allow Your Vet To Perform Incision and Drainage on Your Hamster

When the veterinarian has determined that the lump is indeed an abscess formed by pus collecting under your hamster’s skin, they may need to make an incision with a scalpel and drain out the contents if it has become impacted. This procedure may require anesthetization or sedation, depending on the severity of the abscess.

Suppose the abscess is in the early stages of development and is not causing your hamster any distress. In that case, the vet might opt to prescribe a series of antibiotics that will hopefully disrupt the infectious process.

If the antibiotics are effective, the abscess may not progress, and the pus will be absorbed by the body and excreted naturally.

Learn How To Do Post-Incision and Drainage Care From Your Veterinarian

If the vet decides that incision and drainage is the best course of action, they’ll take a series of steps to ensure that no further infection develops. Once your veterinarian has drained the pus, they’ll then clean the pocket using a saline solution.

The vet will leave you with instructions on performing wound care at home. Follow the instructions and use the prescribed ointments or medications to ensure your hamster’s speedy recovery.

Give Your Hamster Prophylactic Treatment

After the procedure, your vet will most likely order antibiotics to treat the present infection and as prophylaxis of any new infection that may develop.

After all, the excavated abscess is still a break in the integrity of your hamster’s skin and could still be a portal of new infections.

With early diagnosis, timely treatment, and diligent compliance with the prescribed medications, your hamster should be able to recover without complications arising.

The vet may ask you to return for a follow-up. Keep the appointment even if your hamster seems fully recovered.

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How To Prevent Abscesses in Hamsters

You can take preventive measures to minimize the chances of your hamster developing a lump. Routine inspections of its habitat, frequent assessments and general hygiene practices will help you stay on top of any infections that may develop.

Perform Routine Habitat Checks

A regular and thorough inspection of your hamster’s living area can help prevent them from getting scratched or wounded, either of which could consequently lead to the formation of an abscess.

Make sure that there are no sharp edges or objects in the cage that could accidentally cause a break in your hamster’s skin.

Housing your hamster alone will also prevent skin punctures through bite wounds and injuries picked up in fights with other hamsters.

While dwarf species can fare relatively well in groups, individual housing will ensure that bite wounds on your hamster are not a possible means of entry for bacteria.

Check if Your Hamster Has Injuries

It’s also worth going the extra mile of checking your hamster for cuts and abrasions, especially before giving them a sand bath. This added step can help you ensure that your hamster does not get infected.

Sand bath grains could irritate the wound and even embed themselves into it, causing infection.

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Treat Your Hamster’s Wound Before Taking It to the Vet

If, despite the careful preventive measures taken, your hamster somehow suffers a cut or wound, an abscess is not necessarily the certain next step. Treatment of the injury can keep it from getting infected and forming and collecting pus.

First, apply a cotton ball moistened only with warm water to a cut to stop the bleeding. Don’t use disinfectants or antibacterial agents formulated for humans on your hamster, as hamsters have delicate skin that can be easily irritated by these solutions.

After conducting this first aid step and stopping the bleeding, take your hamster to the veterinarian, who will carry out proper treatment and disinfection of the wound. Whether you live in Washington, Nebraska, Idaho, or the remotest areas in the States, you can surely find a local veterinarian who will help you check your hamster and even prescribe a prophylactic course of antibiotics if the severity of the injury calls for it.

Keep Your Hands Clean Before Handling Your Hamster

As your hamster’s primary caregiver, you’re the link between their well-curated environment to the outside world. Always practice thorough hand hygiene before handling your hamster, its food, and other accessories.

Hamsters are small and sensitive creatures. Although they’re hardy creatures, hamsters can quickly become very sick once they’re injured or ill, considering their small bodies.

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A Hamster’s Lump Could Be a Tumor

A lump growing on the body of your hamster could likely be a tumor. Tumors are formed by abnormal cells that divide and grow at an excessive rate. Regardless of species, tumors occur when the body’s ability to inhibit the growth of abnormal cells is impaired.

Your Hamster Might Have a Benign or Malignant Tumour

Just as in humans and other animals, tumors in hamsters may either be malignant or benign. They are masses that form on or in the body due to the grouping of cells that abnormally divide or do not die when they should.

Benign Tumors Are Not Always Life-Threatening

Benign tumors are relatively harmless. They don’t invade neighboring tissues and sites in the body. But while they may be contained, they can grow larger and compress nearby structures, causing pain and affecting a hamster’s mobility and overall quality of life.

Malignant Tumors Are Cancerous

On the other hand, malignant tumors are cancerous and rapidly spread to other tissues and organs of the body through metastasis. Lymphoma, in particular, is a cancerous type of tumor commonly seen in older hamsters.

Lymphoma is curable, but that doesn’t mean it cannot kill. If detected early, you can remove the tumor to prevent it from spreading.

An Early Tumor Diagnosis Is Necessary for Your Hamster

A visible lump growing on the surface of your hamster’s body could more presumably be a tumor if it’s coupled with the following:

  • Skin inflammation (cutaneous lymphoma)
  • Weight gain or loss despite the same measure of food intake (adrenal gland tumor)
  • Strange and unusual actions and movements (brain tumor).

More generalized symptoms such as sudden aggression, excessive sleep, appetite loss, weight loss, abdominal pain, and diarrhea also indicate the lump being a tumor. The first signs of these should spur immediate action and be treated as an emergency.

Imaging technology must be utilized to observe internal tumors. Still, in either case, the veterinarian will need to perform a biopsy on the tumor to diagnose whether it is benign or malignant.

Internal tumors are usually detected too late. Many tumors become palpable in the late stages as some tumors begin in the deeper tissues. But on the rare and fortunate occasion when they are detected early, the hamster’s chances of recovery and survival are significantly increased.

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Different Treatments Are Available for Treating Lumps in Hamsters

Upon diagnosis, your vet may make a referral to a veterinary oncologist if there is one in your locality. They would discuss with you the disease process, available treatment, the treatment they recommend, and the prognosis.

Perform Surgical Removal on Malignant or Benign Tumours

A veterinary oncologist would likely recommend the surgical removal of an internal tumor, whether malignant or benign. The reason for this is that a benign tumor could still grow and affect the hamster’s nearby internal organs, causing pain or the development of more serious complications.

Benign tumors can still be life-threatening to a creature as small as a hamster. An example of this is if the tumor is located anywhere proximal to the airway. A growing lump could occlude your hamster’s airway. The procedure is invasive but potentially life-saving.

Consider Chemotherapy

Chemotherapy is another treatment option that hamsters may undergo. It’s also a more affordable alternative to surgery, given that the drug dosage required would be comparatively much lower than that of other animals.

If the vet recommends chemotherapy and if you agree to the treatment, the vet will let you know about the side effects your hamster may suffer as a result of the treatment. Chemotherapy affects those who receive it quite similar across the species.

The idea is to kill the cancer cells. Unfortunately, perfectly healthy cells may also become casualties of the treatment, which is why people or animals who undergo it suffer discomfort and other excessive side effects.

why does my hamster have a lump on its back
why does my hamster have a lump on its back

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Early Tumour Detection Can Save Your Hamster’s Life

There are, unfortunately, no preventive measures for the growth of tumors and the development of cancer in hamsters. Unlike in humans, where lifestyle practices can be predisposing factors in cancer development, genetics are the primary culprit in the cancer of hamsters.

However, knowing that hamsters are prone to developing lumps, being a vigilant and observant owner could make the difference. Seeking the expertise of the vet could lead to the early detection of a tumor and save the life of your hamster.

Delaying veterinary consultation may delay treatment, and time is of the essence when it comes to more severe diagnoses. In many cases, the factors that cause these conditions to arise were never within the pet owner’s control.

Still, the preventable causes can certainly be minimized by prompt and decisive action.

Don’t Wait Until the Last Minute To Treat Your Hamster’s Lump

The effectiveness of surgery and chemotherapy depends on how early or late the stage of development the cancer is upon diagnosis.

How far along the disease has metastasized upon detection can predict the treatment outcome—the earlier the stage, the better the prognosis and the higher the chances of recovery.

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Owners may observe lumps developing on the bodies of their hamsters. In these rodents, lumps frequently turn out to be either an abscess or a tumor. Specifically, which of the two it is should be determined and verified by a veterinarian through a needle aspirate biopsy procedure.

If your hamster has a lump growing, it’s imperative that you get them checked as the more aggressive tumors typically progress rapidly and result in death within months. On the other hand, the lump may be of a different treatable nature that will still require veterinary intervention.