If your dog sheds a lot it does not necessarily denote ill health. Dogs that spend a lot of their time indoors are exposed to electric lights and central heat and air which can throw off their normal shedding schedule that nature built in. However, profuse shedding may have other causes like an unbalanced diet, a kidney or bladder infection or a parasitic ailment.
If your dogs shedding leads to bald spots you should seek help from your veterinarian as soon as possible. All severe shedding conditions are either parasitic or non-parasitic. Parasitic means caused by parasites such as mites or fleas. Non-parasitic means conditions created by a hormonal imbalance and or poor diet, which can easily be treated with vitamins and a more controlled diet.
Eczema is a symptom of an underlying disorder, usually dietary, rather than a disease. In older animals and altered ones, it may be caused by a hormonal imbalance due to a change of body chemistry. The skin becomes scaly and the hair falls out in patches. You must correct the cause by hormone injections or a change in diet, usually by adding fat supplements of Vitamin A and E.
Eczema can also be caused by fleabite allergy, or a parasitic condition. However, these bald spots usually appear suddenly and resemble lesions, or burns. To treat these, after veterinarian diagnosis, you must eliminate the fleas and use a local application of antimicrobial and anti-inflammatory medicines.
Bald spots can also be caused by mange. There are two types of mange, ot mange, Sarcoptic mange or “Scabies”, which has a musty odor, often starts on the head and spreads to the ears, tail, the abdomen, chest and under the front legs. Skin eruptions may take the form of red dots or blisters, then scabs. Your veterinarian can provide medicated baths; generally sulfur preparations and anti-itch topicals.
The second type of mange is Follicular or Demodectic mange or “red mange”, caused by a different family of mites that burrows into the hair follicles and most often attacks young puppies. Entire litters can be born with it. It is more serious and persistent that the other variety. In the most serious cases, pustules dot the skin where the hair has fallen out. Veterinary treatment will include oral medications and external treatments to kill the mites, but this type of mange takes a long time to cure.
Lastly, he may have contracted ringworm, a contagious fungal infection, (non-parasitic), that grows on hair follicles, rather like athletes foot. It is characterized by ring-shaped red patches covered with scales, and may be dry or moist, usually starting on the head, neck, and legs. Your vet will advise strict anticontagion measures, since it is communicable to humans. Treatments include oral medications, anti-fungal shampoos or dips, and frequent applications of iodine.
Remember, shedding is a symptom of an underlying condition that is best diagnosed by your Veterinarian usually by microscopic analysis of skin scrapings and or blood tests. While bald spots may not be life threatening, the animal is suffering and the conditions usually only get worse with time, so asking your veterinarian for his opinion is more sensible than just worrying about it.