A wide variety of problems may cause a pet to smell bad. They range from simple grooming-related issues to serious medical conditions.

Common Causes

More common causes are listed first. Less common causes are listed later.

• Poor grooming is a leading cause of offensive odors in pets. Many dogs require regular baths. This is less common, although not unheard of, in cats. Animals with feces, food, or debris on their coats often smell bad.
• Dental disease often leads to bad breath. As pets groom themselves, the offensive odor may be transferred to the skin, resulting in a pet that smells bad.
• Skin problems often cause pets to have an offensive odor. These include skin infections with bacteria or yeast, infected wounds on the skin, diseases of the skin caused by the immune system, or wet, matted hair that develops a strong odor. Fleas often contribute to skin problems that cause pets to smell bad.
• Pets with diarrhea may have an offensive smell due to feces adhering to the hair near the anus.
• Ear infections can cause a strong, offensive odor to emanate from one or both ears.
• Bladder infections may cause an offensive odor which is often strongest around the animal's hind end.
• Diseases of the anal glands often lead to a foul odor emanating from the hind end.
• Pets with urinary or fecal incontinence may smell bad as a result of contamination of the hind end. Constipated pets may pass small amounts of feces that adhere to the hindquarters and contribute to an offensive odor.
• Metabolic and glandular diseases such as kidney failure may contribute to offensive odors in pets. In cats especially, any disease that suppresses grooming will contribute to an unusually strong odor.
• In some instances, extremely sensitive owners may feel that their pets have an offensive odor in the absence of any problems. This represents an extreme reaction to the normal smell of the pet. Recommended Course of Action

Consult a veterinarian if no source of the noxious odor can be found by carefully investigating the pet, and if the odor persists despite appropriate grooming and flea control.

Pets with wounds, rashes, ear infections, or signs of illness should receive veterinary attention.

Cats that demonstrate a reduced tendency to groom should be evaluated for illnesses that suppress grooming.

When in doubt, the safest course of action is to seek veterinary attention.

The contents of this page are provided for general informational purposes only. Under no circumstances should this page be substituted for professional consultation with a veterinarian.

Dr. Eric Barchas, DVM, is a veterinarian who lives and works in San Francisco. His emphasis is on small animal medicine, surgery and wellness. An avid traveler, he has studied lions in Botswana and salmon in southern Chile. His site is http://drbarchas.com

Dr. Barchas is also the resident veterinarian of Dogster and Catster. Since May of 2005, he has provided insightful and thoughtful answers to questions from members. His professional advice has added greatly to the wealth of pet health information on Dogster.com and Catster.com from which this column sometimes comes.

"Life...
It is the flash of a firefly in the night,
the breath of a buffalo in the winter.
It is the little shadow, which runs across
the grass, and loses itself in the sunset..."
Crowfoot
Blackfeet Elder