Something that you may not have understood about your dog before are his anal sacs. These two sacs are located in the muscle tissue on either side of the anus at the five and seven o’clock positions. An intensely malodorous secretion, usually brownish and watery in appearance, resides within the sacs.

The anal sac fluid, which emerges through two tiny ducts, serves an unknown purpose in the dog. It may help dogs mark territory or enable them to distinguish one another’s sexual identity, according to different theories. Whatever their purpose, the anal sacs of most dogs can be ignored throughout life. Other dogs, however, are bothered by periodic anal sac problems. They show it by madly dragging their hindquarters across the floor or biting and licking at the tail area. These dogs need to have their anal sacs manually emptied (expressed). A few need to have the sacs surgically removed.

How often may your dog’s anal sacs need to be expressed? This depends on whether your dog is one who suffers from bouts of impaction or from actual anal sac infections. Some dogs need monthly attention, while others can go several months without a problem. This is best discussed with your veterinarian, especially if anal sac impaction affects your dog. Should you feel you want to empty the anal sacs at home, here are some guidelines.

1. Begin by standing the dog on a firm surface. The floor will do fine with a large dog, while a table (with surface protected) may be necessary to express the sacs of a small dog. Hold a piece of cotton or paper towel in one hand to cover the anal area. This is useful because the secretion usually squirts out from the ducts once pressure is applied over the sacs.

2. With the absorbent material in place, put your thumb on one side of the anus and your index finger on the other. Gently squeeze your fingers together until the contents of the sacs begin to emerge from the ducts. Usually, the secretion is quite watery, but if it’s been retained for a while, it may resemble toothpaste. Don’t use excessive force, or you may rupture the delicate sacs.

3. Another method of expressing the anal sacs involves inserting your gloved and lubricated forefinger into the anus and feeling for each anal sac individually within the sphincter muscle. Then, grasping it between your thumb and finger, gently press on the sac until the fluid is released. This procedure should not be painful but it may be uncomfortable for the dog, so you’ll probably need somebody to hold the animal.

If you find that the secretion won’t budge, first try redirecting the pressure. Occasionally, the sacs will be completely impacted and then it’s time to see the veterinarian. This also holds true for secretion containing pus or blood, which indicates an infection of the anal sacs. If not treated promptly, they could become abscessed, which is very painful. Anal sac infections are frequently treated with oral and local antibiotics. The latter is inserted through the ducts into the anal sacs themselves.