Overview of Skin Discharge and Odor in Dogs
Skin odor is a common manifestation of a skin infection. The most common skin infections are bacterial (superficial pyoderma) and yeast (Malassezia dermatitis) infections.
The bacterial infections are usually caused by bacteria that are part of the normal flora of the skin (e.g. Staphylococcus intermedius). For this reason the infection is not contagious to other animals. In dogs that have abnormal skin (e.g. allergies) the bacteria increase in number and cause red bumps (papules) and rancid odor. Some dogs with bacterial skin infections also develop excessive shedding, patchy hair loss and scaling. If the infection is left untreated, involvement of deeper parts of the skin is possible. In these cases nodules that have a purulent (pus) discharge develop. In most cases skin infections are secondary, so it is very important to pursue an underlying cause. Failure to do so will result in recurrent infections.
Animals often develop a yeast infection (Malassezia dermatitis), which manifests itself as greasy, red, itchy skin with a rancid odor. Areas most commonly affected include the ventral neck, groin, armpits (axillae) and perineal areas. This infection is also secondary to an underlying disease, most commonly allergies. In some dogs this may be a consequence of chronic antibiotic and steroid therapy but, as a general rule, dogs do not develop yeast infections after antibiotic therapy as commonly as people do.
Diagnosis of Skin Odor and Discharge in Dogs
Treatment for Bacterial Dermatitis
Treatment for bacterial skin disorders is antibiotics. Some of the more commonly used antibiotics include ampicillin, cephalexin, enrofloxacin, clindamycin, clavulinc acid and sulf based drugs. Other treatments may include:
Treatment of Malassezia Dermatitis
You will need to shampoo your dog with medicated shampoos. Benzoyl Peroxide is an excellent antibacterial antibiotic (e.g. Oxydex®, Pyoben® shampoo). Other antifungal shampoos contain miconazole or ketoconazole (e.g. Nizoral® shampoo for dandruff is now available OTC).
Contact time is important when using a medicated shampoo. You should allow a 10 to 15 minutes contact time for the product to be effective. Leave-on products are also available on the market for prolonged efficacy.
You may have to administer oral medications (either antibiotics or antifungal medications) to help treat the infection. Compliance is very important. Some dogs may require medications for a prolonged time as skin infections usually take a while to clear.
If your dog keeps relapsing with infections, it is important to pursue an underlying cause. This will decrease the frequency of relapses and reduce the risk of resistance to medications used for prolonged periods of time.