How to Drain a Cyst on a Dog

How to Drain a Cyst on a Dog

It’s tempting to consider how you might drain a cyst on a dog from home. They sometimes look a bit like pimples, although they can get to be the size of a golf ball in some cases.

Unfortunately, draining a cyst on your dog without medical intervention can cause pain while leaving your dog vulnerable to a skin infection.

Cysts can be something like pimples.  They most commonly occur on the skin and are filled with fluid. Some cysts will actually come to a head and erupt on their own. Most of the time, if the cyst isn’t bothering anything, it’s best to leave them alone.

This post will give you a better understanding of why you shouldn’t drain a cyst on a dog, why you should get a veterinary evaluation, and what to do if the cyst ruptures by itself.

What is a Benign Cyst?

A cyst is a general term used to describe a fluid-filled lump under the skin.

Cysts develop from hollowed-out cavities within the body.  The body finds hollowed out cavities in tissue and, because the body is good at taking care of business, works to fill in those spaces.  

Cysts, somewhat like calluses and blisters, act as a protective buffer around injured tissue.  In some cases, dogs develop cysts internally on or around organs.

Examples of different types of cysts include the following:

True Cyst

A true cyst is non-inflammatory and contains a lining known as an epithelium.  This lining is made up of secretory cells that discharge fluid into the cavity.

 The big difference between a “true” cyst and other cysts is that this type isn’t formed by the accumulation of pus.  

False Cyst

A false cyst does not contain a secretory lining. These usually occur due to an injury of the tissues.  In many cases, these cysts wall themselves off and are not a bother.

Follicular Cysts 

Just as the name implies, follicular cysts develop around dilated hair follicles. A follicular cyst can be considered sebaceous or epidermoidal. 

Sebaceous Cysts

A sebaceous cyst is a common occurrence in older dogs.  They occur as a result of inflamed hair follicles.  The over-production of sebum (oily substance) on a dog will have one of three results:

  1) It will dissolve on its own.

  2) It will rupture naturally.  

3) It will wall itself off. When it walls itself off, it may stay the same size and maintain the same appearance.

You should know how to drain a cyst on a dog
Thank you caleb-fisher-pgUbpDLJh3E-unsplash


Dermoid cysts only happen in utero. In this case, the cyst develops within the body of the unborn puppy.  It’s possible for the dog to live a long time before anybody realizes it’s there.

Will Your Veterinarian Drain a Cyst on a Dog?

Veterinarians are highly skilled professionals. They are the only people who should attempt to drain a cyst on a dog. Even though they know how to drain a cyst on a dog, it doesn’t mean they will. 

Once the veterinarian has determined that your dog has a benign cyst (after microscopic examination) the decision to surgically remove would depend on the comfort and safety of the dog.

If the cyst is very large (some grow to the size of a golf ball or larger) and is uncomfortable for the dog, the vet may opt to surgically remove it. Small, uncomplicated cysts are typically left alone. 

How to Treat a Ruptured Cyst on a Dog

If your dog’s cyst doesn’t go away, but instead erupts, you’ll need to take care of the wound. It’s important to keep it open and draining freely to get all of the fluid out.  

A warm compress should be applied to the draining cyst for up to 10 minutes, two or three times a day.  At this stage, it’s important to watch for signs of infection.  

Simple Products I Have Used to Clean my Dog’s Ruptured Cyst


I recommend having a Beauty Pro Hot Towel Warmer on hand. It keeps towels perfectly warm for a long time and can be used for a variety of things.

Hibiclens Surgical Scrub

This scrub can either be applied to warm towel and used as a compress, or it can be diluted and used to gently wash the area. Personally, I use it both ways.

Signs of infection could include additional swelling around the cyst, redness, pain, pus, and a foul smell from bacteria/yeast.

The idea is to keep the liquid draining until it is all gone.  Keeping the area moist will prevent a scab from forming.  When a scab forms, the remaining fluid is trapped inside. This can cause a bacterial infection, or can cause the cyst to reoccur.

Be sure to swab the wound with a bacterial cream or wipe several times a day.   

The most difficult part of this is keeping your dog’s mouth away from the wound.  The best suggestion is – of course – the Elizabethan collar. These days, there are a lot of variations that might prove more comfortable for your dog.

Open Cyst Drainage

Doctors may decide to perform open cyst drainage surgery if the cyst has become infected.  That decision will depend on the health of the dog. These types of cysts tend to develop in older dogs.  General anesthesia could put your dog in a risky situation where heart failure is possible.

This procedure is especially useful in reducing the pain and pressure of a large cyst.  It must be done in a sterile environment, such as the animal hospital or clinic.

If the veterinarian feels your dog is strong and healthy enough, he/she may decide to go ahead with the removal.  The first thing will be to put your dog under general anesthesia.  

The surgeon will cut into the skin to expose the cyst.  He/she will then slice an opening to allow the pus (if it’s infected), keratin, or sebum, to drain.  

The surgeon will monitor your dog while he or she is under.  Once the fluids have completely drained, the surgeon will then cut out the remaining sac of tissue.  Your dog will be sutured and sent home to rest.  Again, in my experience, one of the hardest things to do is keep the dog from messing with the incision,

The veterinarian may send you home with antibiotics for your dog.  If so, make sure to give your dog the full prescription as indicated.  

When people stop antibiotics early, bacteria could come back.  The second time this happens, the bacteria are stronger. The more this cycle continues, the greater the risk of developing antibiotic resistance.  

Take Courses and Learn the Basics of Grooming, First Aid, and Behavioral Training

Caring for an ill dog requires a variety of skills including basic first aid, keeping a dog calm, physical therapy, gentle massage, and many other skills. There are many short courses offered by seasoned professionals that can give you the confidence you need through confidence.

The more you can do at home, the less money you need to spend on extra care.

Browse the list courses and sign up today.

Dog Behavioral Training Courses

Sign up for short-term courses that help you take better care of

your dog for less money.

Risk of Bacterial Infection

Popping a cyst on a dog is painful to the dog and could worsen the condition. 

The risk of infection goes up when it’s popped superficially.  In fact, you risk pushing the fluid deeper into the tissues (which could cause another cyst to appear). The open wound is then subject to bacterial infection.

Even if you insist that you know how to drain a cyst on a dog, you should still get medical assistance.  Draining it with a small needle puncture is going to be painful for the dog, and messy for you.

Be prepared for a foul smell and a period of drainage that will require keeping your dog from licking the open wound.

How to Tell if it’s Just a Cyst, or Something Else.

The only way to tell if it is a benign cyst or cancer is to perform a fine-needle aspirate or tissue biopsy. 

Veterinarians, however, are highly skilled professionals who can probably detect a cyst from a tumor a mile away.   Even so, they can’t give an absolute diagnosis without looking at it first.

Some telltale signs that it is a benign cyst and nothing more include the fact that it is easy to move. A benign cyst will be soft, painless, and easy to move around.  

In addition, benign cysts are common in aging dogs.  A dog is considered senior at seven years of age.

Is Your Dog Just a Puppy?

Cysts can still occur in younger dogs.  Sometimes, however, they are more likely to appear as the dog ages.

When a puppy gets a cyst, it is usually considered genetic. This is called a dermoid cyst and they usually develop before the puppy is even born. They are considered rare.

Dog Breeds Prone to Cysts

The dog breeds most prone to various types of cysts include:

Mexican Hairless

The Mexican Hairless comes in a toy, mini, and standard sized variety. These dogs are elegant but active. They make good watchdogs, but not guard dogs.

Chinese Crested

The Chinese Crested is also a hairless dog. This dog is affectionate, lively, and playful.

Rhodesian Ridgebacks

AKA the African Lion, this dog was designed for hunting and guarding.  

Cocker Spaniels

The Cocker Spaniel was designed as a hunting dog.  They’re lovely and love to play.

Could it be Cancer?

Tumors can be malignant or benign.  Malignant tumors in dogs grow quickly, express discharge, and can suddenly change shape, texture, or color.

If it does turn out to be a tumor, thank your lucky stars you found it early.  The general rule of thumb is that the earlier you spot a tumor, the greater chance of success.


Why You Shouldn’t Worry

If you’re anything like me, you’ll poke and prod at that cyst until you drive yourself insane. You’ll compare it to images on the Internet and might even take pictures of your own to share with others.

If you have seen a veterinarian and that person has confirmed it is a cyst, you can stop worrying.  The veterinarian may have suggested leaving it alone.  A cyst will either dry up on it’s own, or continue to grow until it ruptures.  

My Own Experience

I recently went through a situation like this. My senior lab developed a lump on her chest. It wasn’t on or in the nipple, so I knew it wasn’t mammary cancer. 

It was smooth with a margin all around.  The center of the cyst had a dark line, as if there were dark pus inside.

The veterinarian was very confident that it was a benign cyst. She didn’t do a fine-needle aspire or a biopsy. Instead, she told me to watch it.  “If it doubles in size over the next month, bring her back.”

That was three months ago. The cyst is still there,  but it hasn’t grown. It doesn’t hurt and there’s no sign of infection.

Read More About The Differences Between Cysts and Tumors HERE

Prevent Cysts from Returning

There’s no guaranteed way to ensure your dog will not get any more cysts. However, there are some thing you can do to lessen the risk.

The only sure way to prevent cysts is to avoid injury to your dog. Dogs run and play, they jump and bump.  It’s impossible to keep a dog from encountering minor injuries, especially if you have an active and healthy dog.

Learning everything you can about cysts now will ease future worry should it happen again. Next time around, you’ll have more confidence and knowledge.

Thank you for reading and please share!

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