My dog has a sore, swollen spot near his rectum. What could it be?

Thank you for providing pictures of Madden's anus for me to see. From the pictures, it could be that he has a rectal prolapse, or he could have impacted anal sacs causing this redness and swelling. The best thing to do is take him into a vet as soon as possible. The vet can diagnose what is causing this redness and swelling, and can treat him for it. Good luck, I hope this helps!

I would recommend that you have your dog evaluated by a veterinarian. Possible causes of wounds in the area that you mentioned can be caused by anal gland infection or abscess, perianal fistula, or wounds caused by excessive scooting - which can be caused by intestinal parasites or allergies (fleas, food, environmental, etc). Until you can have your dog evaluated by a vet, it may need to wear an e-collar or cone to prevent licking these areas. Licking will spread bacteria and delay healing.

Dogs do not get hemorrhoids. This could be a skin infection or an anal gland infection. Unfortunately there is also a possibility that your dog may have a beginning tumor at this site. The earlier such conditions are treated the more likely they can be cured. You will need to schedule an appointment with your vet to have this examined. At best it is just a harmless skin change, but there is no way to determine that from a photograph.

It's a little difficult to tell from your picture alone - being able to examine and touch a lump in person makes it much easier to determine what it is. This could be a skin tumor, a small abscess or inflammatory nodule, or a lesion from something like contact hypersensitivity. I would recommend having this lump examined by your veterinarian since it looks red and possibly like there is discharge. If he is licking or chewing at the lump you should put an e-collar on him until you can see a veterinarian. They may know what it is after being able to examine it or may recommend taking an aspirate sample using a small needle to look for cells under the microscope.

Red’s anus does look irritated and I can see some redness on the underside of his tail as well. He might be licking due to irritation from full anal glands, parasites or allergies. I would recommend having your vet examine him and check his anal glands. They may want to check a stool sample as well. Oral or topical medications might help. I would recommend putting an e-collar on to prevent licking until you can get to the vet.

You had asked what might cause this -- possibilities include an [anal gland abscess](https://www.petcoach.co/article/anal-glands-sacs-impactions-infections-abscesses-in-dogs), [other infection](https://www.petcoach.co/dog/condition/skin-ulcers-and-draining-lesions/) or possibly a tumor. Unfortunately, without a physical exam, a diagnosis cannot be made. Your veterinarian should be able to diagnose the cause after the exam tomorrow. Until then, place an [e-collar](https://www.petco.com/shop/en/petcostore/product/well-and-good-e-collar) (cone) on your dog to prevent licking or chewing. Any treatment will depend on the diagnosis. It is likely the e-collar will need to be kept on until healing is complete.

Many things can cause redness around the rear end. Common problems I see are irrigation due to seasonal allergies, infection of the anal sac, and sometimes skin infections or tumors. If it seems painful or is not improving I would recommend he be seen by a veterinarian. Thanks for using Pet Coach