Sebaceous Cysts In Dogs And Cats

Sebaceous cysts are interesting structures.

All pores and hair follicles in the skin are surrounded by microscopic oil glands. These glands produce the oil that makes our pets’ hair (and our own hair) shiny, as well as producing a protective and moisturizing layer for the hair and skin. This oil is called sebum.

Sebaceous cysts occur when a normal pore or hair follicle becomes occluded. Occlusion can occur from dirt, infection, scar tissue or even normal sebum that becomes too thick to move out of the pore’s opening.

As long as the cysts are small, closed and intact they cause no problems.

Please do not squeeze them.

Sebaceous cysts become problematic when they burst and become open to the outside world again. Frequently then they become infected and must be removed surgically. Surgical removal becomes necessary when the cyst will not heal with topical and systemic antibiotics and/or irrigation.

Sebaceous cysts may also rupture under the skin and spill their oily contents into the surrounding tissues. The result is an intense inflammation causing a red, itchy area the pet is likely to lick, scratch and rub. These lesions may even be confused with a lick granuloma because both are highly inflamed and very itchy.

Early sebaceous cysts are usually white, raised and quiet-looking. As long as they stay in this phase they require no medical treatment.

It is when complications occur and they become inflamed that medical and/or surgical attention is needed for sebaceous cysts.

See you tomorrow, Dr. Randolph.

sebatious, sebacious


  1. My American Eskimo had a sebaceous cyst on her tail. It ruptured and she now has this hole. It bleeds and forms a scab, however every time I go to check on it (about once a week) the scab pops right back out and the process starts all over again. It is not infected and I never see her chewing on it. It is as if the hole will not close. What would need to be done to get it to finally heal? Is surgery the only option at this point? It has been about three months now. It does not bleed a lot. Just enough to clog the whole. Appreciate your advice.

    • Ctrl-F while on the page the post is on, and type in “foreign” to the resulting search window. This lesion may or may not be infected, but the foreign-body reaction will probably have to be surgically excised in order for the lesion to heal.

  2. Hi Dr. Randolph. My 10 y.o. Bullmastiff recently had surgery to have two sebaceous cysts removed after they had opened up. One from the top of his head, and one from his left hip/butt area. After surgery he was prescribed Tramadol for pain and Rovera for inflammation. Day 1 he seemed ok, definitely had trouble walking (we assumed from the cyst removal on his hind leg/hip), he was breathing VERY heavily and was sedated for a while from the meds. By day 3 we felt the meds were making him worse. He was still having trouble walking (vet said this would be better after day 2), loss of appetite and panting for long periods of time. Worried, I called the vet and she said to stop the meds and see how he does. Now he doesn’t seem to be in pain, but his breathing is still heavy, he is having trouble walking and maintaining balance, he has lost interest in his food (and ours) and we don’t know what to do. ): I’m scared to death that we did this to him by having him undergo surgery. We are taking him to the vet tomorrow, but I don’t think I can sleep without knowing he can AND WILL get better. Please help!!!! ):

    • I’m sorry I was delayed getting to your question. Certainly he needed re-examination and re-evaluation, and, possibly, a chest X-ray. Can you write back and tell me how he’s doing now, and what the doctor found on the followup?

  3. I don’t think my dog is suffering from a subacious cyst,but I don’t know so….
    I have an 8yr old pitbull,Rufus, and this morning he was perfectly fine. This afternoon he spent about 2hrs outside and it was very hot. I went to bring him inside and right away I felt something was wrong. He has this swelling from his collar to his tail along his spine on both sides and spreading a couple inches down his sides from his spine. There are no noticeable lumps, bumps, bites,or lesions. But all the way down in several spots there is a clear-ish blood-tinged fluid, (not like puss), that seems to be seeping from his pores. He is very obviously in pain and flinches at the lightest touch. There is nothing in the yard that would’ve caused this, and I have another pitbull, 4yrs old, who was in the exact same spot for the same amount of time, although not at the same exact time, and she is fine. Please help me. Does he need a vet? Does this sound like a serious condition requiring medical attention?

  4. I have 6.5 y.o. miniature schnauzer girl (dog). She was diagnosed with 2,5×3 cm cyst that grew up on her left hip over 3 years.
    After biopsy was done, we scheduled a surgery in 3 weeks, but cyst ruptured under the skin that caused the inflammation.
    It opened up a week before surgery and started releasing puss and blood. Past Friday (06/24/16) vet performed a surgery cleaning up the site.
    When I came to pick her up, I saw the scar on her leg 2,5 inches long, going right under original cyst. But it looks like original cyst was not open (no scar over the cyst and original area is still steaking above the skin level). I asked the vet about this issue and she said that she made the cut and cleared everything around (everything under loose skin). The dog is on antibiotics right now and on pills to prevent pain and inflammation.
    Nevertheless, I still see that area above her scar is slightly swollen and it borders me.
    I am wondering if cyst ruptured under the skin, did it release all puss and would it be possible/enough to clean it up without cutting the cyst site itself but inflammation only?
    Or, cyst is still there? May it heal up as is?
    What to ask vet about?
    We are going to see her in a week from now(week after surgery)

    • Gee, Elena, I’m really sorry, but I just don’t have enough information to be able to answer your questions. Even seeing the patient probably wouldn’t give us all of the answers, because some of what you’re asking about happened down inside the tissues, where no one can see. I wish I could have been more help. Thank you for reading, Dr. Randolph.

  5. I have a 18 year old cat that keeps developing cysts. The 1st time the vet was going to do a biopsy, but when she stuck a needle in fluid came out, so she said it was a cyst and it drained. After a couple of months it came back larger than before. I had this drained again and it came back larger again, within a week. The 3rd time she drained it with a larger hole and had us clean the hole to keep it open as long as possible. It closed up from the inside out and now the cyst has come back, fairly large (over 2 inches)and it seems to bother her. She has torn her skin off from scratching it. The vet doesn’t want to do any kind of major surgery because of her age. Not sure what to do at this point.

  6. hi
    My lab just had a large lipoma removed on his FRONT leg only because it split and burst out of his leg. We had no choice. however since the op he has become lame on his BACK leg and drags his foot ., he also slips over as the leg gives way , We have spent a fortune on various pills including steroids to no avail.The vet tells me the surgery possibly has caused an ageing effect . Any advice please?

  7. I have a 12 year old golden retriever who has suffered from atopic allergies since she was 2 years old. For the last 3 or 4 years, she has been on Atopica, and Temaril P when there is a flare up. In the last 3-4 years, she has developed sebaceous cysts of massive size, that even amaze her Vet. Due to her age, and the fact that the cysts don’t seem to bother her, we don’t have them removed. Only 3 have opened, and I’d say she has a dozen or more on her. 2 of the ones that opened resolved themselves with the help of an antibiotic. The one on her tail is very large and oblong, filled with a lot of clear fluid and scar tissue. It has a little larger than a pin size opening now, that almost works like a pressure valve, keeping the size from growing any more. No inflammation is seen. My adult children laugh at it, calling it her testicle, which is exactly what it looks like..ugh. My question is, should I put light pressure on this cyst to remove the clear liquid? At times, when full, if I so much as touch the cyst, the fluid comes out of the small hole with such force that it will shoot 3 or so feet, so there is obviously pressure on the skin.

    • “filled with a lot of clear fluid and scar tissue” is odd behavior for a sebaceous cyst. I understand your reluctance to have a biopsy performed because of her age. Without it, though, it’s hard to provide specific advice. As stated above, though, I don’t like squeezing them for the reasons stated.

  8. Hello. I will truly appreciate some advice. We took our Basset to the vet to remove a cyst on her shoulder. They made a cut in a shape of a cross below the cyst and told us the cut will remain open in order for the fluid to drain. This does not seem right to me. Is this normal? They also told us that we are not allowed to close the wound and that it needs to dry out. However, our dog keeps scratching at it, which makes the wound bleed and grow in size.
    Please help.

  9. I have a 7 year old daschund named Toby. He has a spot on his head that for many, many months now has shown up and then disappeared. It is the color of his skin which is black. It will fill up and when it does, it is soft to the touch, but looks about ready to burst…it never actually bursts though. Eventually it will begin to grow smaller and smaller until it is flat and all tou can see or feel, is a tiny stretched piece of skin….a few weeks later it will fill up again….repeat in same manner over and over. At first I was worried and wanted to rake him to the vet but didn’t have the money….then when it started draining and coming back, I am curious….it doesn’t appear to hurt him at all! And other than the swelling while it is filled it has never gotten any bigger…..

  10. Thank-you for taking the time with my question. I have read your previous posts and would like to ask: once a benign cyst (1/2 dollar size, previously diagnosed and vet told us to leave it alone) ruptures on its own at home,(it was clear with some tiny white fragments) and has stopped bleeding, can my dog’s vet stitch the two round open holes it left open together under local anthesia? The cyst area in on a 50lb golden retriever, age 10. I don’t want her to go under anethesia if this will heal with a few stiches now. Since it has ruptered and dranined, will it fill up again? I cleaned it and put a gauze bandage over the holes until she sees the vet Monday. Thank-you

    • Alyson, these are all questions your attending veterinarian can answer for you. He has examined your pet; I have not. He knows his capabilities and preferences; I do not. I do hope that you will write back to us and let us know the outcome of your pet’s experience. Best wishes, Dr. Randolph.

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