Avon Animal Hospital

19475 Fraser Hwy V3S 6K7 Surrey, British Columbia
Phone: (604) 532-7600

Medical Anal Gland Problems

Our Veterinarian at Avon Animal Hospital in surrey, Recommend anal glands should be expressed every six to eight weeks or sooner if needed and always watch for signs explained below to avoid costly surgical procedures.                      

Location and function of anal glands

Illustration of anal area As the dog or cat is viewed from behind, anal glands (also called anal sacs) are located on each side of and slightly below the anal opening, at the 4 o'clock and 8 o'clock positions. A tiny duct or tube leads from the gland under the skin to an opening directly beside the anus. 

All predators, whether they are canines or felines in the wild or skunks in your backyard, have anal glands. They just use them differently. Skunks discharge the secretion from these glands as a form of defense, while dogs use it primarily for territorial marking or as a form of communication. In dogs and cats, every time a stool is passed, it should put enough pressure on the anal glands that some of the secretion is deposited on the surface of the stool. Other dogs and cats are then able to tell who has been in the neighborhood, just by sniffing the stools they find. Additionally, dogs and cats recognize each other by smelling each other in the general area of the anus, since each animal's anal glands produce a unique scent.

Anal Gland Disease in Dogs and cats

Anal sac disease is the most common disease entity of the anal region in dogs. Small breeds are predisposed; large or giant breeds are rarely affected. In cats, the most common form of anal sac disease is impaction

Anal sacs may become impacted, infected, abscessed, or neoplastic. Failure of the sacs to express during defecation, poor muscle tone in obese dogs, and generalized seborrhea (which produces glandular hypersecretion) lead to retention of sac contents. Such retention may predispose to bacterial overgrowth, infection, and inflammation. 

Signs of Disease

Signs are related to pain and discomfort associated with sitting. Scooting, licking, biting at the anal area, and painful defecation with tenesmus may be noted. Induration, abscesses, and fistulous tracts are common. In impaction, hard masses are palpable in the area of the sacs; the sacs are packed with a thick, pasty, brown secretion, which can be expressed as a thin ribbon only with a large amount of pressure. When the sacs are infected or abscessed, severe pain and often discoloration of the area are present. Fistulous tracts lead from abscessed sacs and rupture through the skin; these must be differentiated from perianal fistulas. Anal sac neoplasms are usually nonpainful and are associated with perineal edema, erythema, induration, or fistula formation. Apocrine gland adenocarcinomas of the anal sac are typically seen in older female dogs. These dogs may be presented for signs secondary to hypercalcemia, such as polyuria and polydipsia, or for problems related to the perineal mass.


Diagnosis of impaction, infection, or abscessation is confirmed by digital rectal examination, at which time the sacs can be expressed. Microscopic examination of the contents from infected sacs reveals large numbers of polymorphonuclear leukocytes and bacteria. A tumor should be suspected (anal sac apocrine adenocarcinoma) in anal sacs that are firm, enlarged, and nonexpressible even with irrigation. Ultrasonographic examination may be useful to determine whether a firm, nonexpressible anal sac is due to infection/abscessation or neoplastic disease. In the case of a suspected tumor, the diagnosis should be confirmed by biopsy. Regional and systemic metastasis should be evaluated, and serum calcium measured. 

Anal Gland Expression /Flushing/Surgery/medical treatment/Prevention

Impacted anal sacs should be gently, manually expressed.  If our veterinarian or nurse find out contents are too dry then A softening or ceruminolytic agent or saline can be infused into the sac. Then our nurses or veterinarian at Avon Veterinary hospital  cleans the  glands  with antiseptic, followed by local and systemic antibiotic therapy.

Anal gland abscesses must be lanced by a veterinarian, and antibiotics are usually given to the pet for seven to 14 days . Hot compresses, applied every 8–12 hr for 15–20 min each, are beneficial for abscesses. Repeated weekly flushings combined with infusion of a steroid-antibiotic ointment may be needed. Adding supplemental fiber to the diet may increase fecal bulk, facilitating anal sac compression and emptying. If medical treatment is ineffective, or if neoplasia is present, surgical excision of the sac is indicated. The closed technique for excision is preferred and has the lowest complication rate. However, fecal incontinence, a common complication of anal sac surgery, may result from damage to the caudal rectal branch of the pudendal nerve and may be complete if damage is bilateral. Chronic fistula formation may be seen when sac removal is incomplete or when the sac ruptures. Scar formation in the external anal sphincter may result from surgical trauma and result in tenesmus.

Prevention may help;

Dogs with recurrent anal gland impactions are often placed on a high fiber diet. The high fiber makes the animal's stool more bulky. The stool will put more pressure on the anal glands as it is passed, and hopefully the glands will express themselves when the animal defecates. There are several commercial brands of high fiber dog food available. Animals may also be supplemented with bran or medications such as Metamucil which will increase the bulk of the stool..