My dog has a red, inflamed sore under his bum. Is it normal?

Based on the location I would guess that this might be the draining tract from an anal gland abscess. Anal glands can become impacted or infected and an abscess can form that ruptures to the skin. You should see a veterinarian who can confirm the diagnosis and prescribe antibiotics and pain or anti-inflammatory medication as needed. Sedation to flush the glands might be required.

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.

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

I would recommend that you have it checked out by a vet. From just your description, what you may be seeing could be a perianal fistula, an abscess, and infected anal gland, a rectal prolapse, a wound caused by scooting or excessive licking, etc. Prevent Roscoe from licking, and if you see him scooting then he may need to wear a doggie diaper to prevent further damage to the area. If you can take a picture and attach it to a new post, we may be able to help you a bit more.

Either is possible - diarrhea can cause irritation and 'itchiness' of the anus and perianal area. Baxter's anal glands could also be full since they are normally emptied during defecation and his stool probably hasn't been bulky enough to express them. If his anal area looks irritated you could apply a thin layer of Vitamin A+D ointment or Petroleum jelly to the area, but if he keeps scooting I'd recommend taking him in to have his glands checked.

Thanks for using Petco Pet Education Center, formerly Petcoach! This is likely due to an infection of the anal sac or possibly allergies for example. I highly recommend that you have him evaluated by a veterinarian for further assessment and treatment. Best of luck!

This could be a severely abscessed anal gland/sac or a tumor or a perineal hernia. This can only be diagnosed with a hands-on exam. You should have it examined by your veterinarian, as it is not possible to distinguish these by just looking at a photo. An abscess can usually be treated with antibiotics and/or be lanced, and a hernia may have to be fixed surgically. To identify a tumor, your vet may want to do a fine needle aspirate (he takes some material from the bump with a needle and then looks at it under the microscope) to determine whether the mass is concerning.