If you have a brown Shih Tzu that is gradually turning white, you may be wondering why this is happening. Color changes in a dog’s coat can occur for various reasons, most of which are natural and nothing to worry about. However, in some cases, coat color changes can indicate an underlying medical issue that needs veterinary attention.
Normal Coat Color Changes
Many dogs experience natural coat color changes as they age. These age-related color shifts are especially common in certain breeds, including Shih Tzus. Here are some normal coat color changes you may see in an aging brown Shih Tzu:
- Gradual lightening of the brown coat over time
- Development of stray white hairs, especially on the face and paws
- Fading of the brown coat to a silvery-gray or cream color
- Whitening of the muzzle
These coat color changes are a normal part of the aging process in many dogs. As melanin production in the hair follicles decreases with age, brown coats tend to lighten over time. The first white hairs usually appear on the muzzle and face, then gradually spread to other areas. An elderly Shih Tzu with a mostly white coat likely had a brown coat as a young dog.
Vitiligo
Another common cause of coat color change in Shih Tzus is vitiligo. This condition causes depigmentation and whitening of areas of skin and hair. It occurs when melanocytes, the cells responsible for producing the pigment melanin, are destroyed. Vitiligo usually first appears at around 3 years of age and causes symmetrical whitening of the dog’s coat.
Common signs of vitiligo in Shih Tzus include:
- Whitening around the muzzle, eyes, belly, and genitals
- Bright white patches on the neck, back, and tail
- Whitening of paws
Vitiligo is not harmful to your dog’s health. However, dogs with vitiligo are sensitive to sunburn on depigmented areas of skin. Use doggie sunscreen when outdoors and limit time in the sun.
Cushing’s Disease
If your Shih Tzu is rapidly turning white before age 5, it could be caused by Cushing’s disease. This endocrine disorder happens when the adrenal glands produce too much cortisol. It most often strikes middle-aged and older dogs.
Signs of Cushing’s disease include:
- Extreme thirst and urination
- Increased appetite
- Pot-bellied appearance
- Thinning skin
- Hair loss
- Panting
- Lethargy
The high cortisol levels caused by Cushing’s disrupt normal hair growth cycles. This can lead to symmetrical hair loss on the body, causing the coat to rapidly whiten. Cushing’s disease requires lifelong treatment with medication, so see your vet if you notice these symptoms in your Shih Tzu.
Hypothyroidism
An underactive thyroid gland can also cause coat changes in Shih Tzus. Hypothyroidism happens when the thyroid gland doesn’t produce enough thyroid hormone. This condition is most common in middle-aged and older dogs.
Signs of hypothyroidism include:
- Lethargy
- Weight gain
- Cold intolerance
- Dry, dull coat
- Hair loss
- Darkened skin
The hormonal changes of hypothyroidism can cause rapid whitening of the coat. Patches of hair loss may also occur. Daily thyroid medication can resolve these coat changes and other symptoms once the correct dose is established.
Nutritional Deficiencies
Certain nutritional deficiencies can lead to premature whitening and coat changes in Shih Tzus. Deficiencies of vitamins, minerals, amino acids, and fatty acids can disrupt melanin production and normal hair growth.
Common nutritional causes of coat color changes include deficiencies in:
- Protein – Causes fragile, thinning hair
- Zinc – Impairs hair growth
- Copper – Causes coat discoloration
- Vitamin B6, B12, and folate – Associated with lightening coats
- Iron – Can lead to bald patches and hair loss
Ensuring your Shih Tzu’s diet contains adequate amounts of these nutrients can help prevent premature whitening. Your vet can recommend supplements if blood tests confirm any deficiencies.
Skin Infections and Parasites
Certain skin conditions in Shih Tzus are linked to coat color changes and hair loss. These include:
- Demodectic mange – Caused by mites burrowing into the skin
- Bacterial skin infections – From Staph bacteria or dermatitis
- Ringworm – A fungal skin infection
- Flea allergy dermatitis – Severe reaction and itching from flea bites
These skin problems cause inflammation, itching, and damage to hair follicles. This can lead to whitening of the coat in patches or across the whole body. Treat the underlying skin condition with medications from your vet to resolve the coat changes.
Stress or Trauma
Stress and trauma can have surprising effects on coat color. Some Shih Tzus may start growing white hair after stressful experiences like:
- Being re-homed
- Losing a companion pet
- Being attacked or hurt
- Spending time at a shelter or boarding facility
In these situations, stress hormones and other factors disrupt the normal hair growth cycles, causing temporary whitening. The coat color often returns to normal once the stress is relieved and hair regenerates over the next few months.
Diagnosing the Cause of Coat Color Change
If your brown Shih Tzu is rapidly turning white before age 5, be sure to see your vet. They can perform tests to pinpoint the underlying cause:
- Physical exam to check skin, hair quality, and look for parasites
- Blood tests to check thyroid levels and other hormones
- Skin scrapings to test for mites or fungal infections
- Biopsies of affected skin for analysis
- Ultrasound or CT scan to evaluate the adrenal glands and abdomen
Based on your Shih Tzu’s exam and test results, your vet can diagnose and treat any medical conditions causing the coat color change. They can also advise you on supplements to improve hair and skin health.
Home Care Tips for a Whitening Coat
While you’re working with your vet to determine the cause of your Shih Tzu’s coat change, here are some tips for caring for a whitening coat at home:
- Brush frequently to remove dead hairs and prevent matting as the coat whitens.
- Bathe monthly with a moisturizing shampoo to hydrate the skin and hair.
- Protect exposed pink skin with dog-safe sunscreen.
- Supplement with omega fatty acids to boost skin and coat health.
- Try a whitening shampoo to brighten the coat as it lightens.
- Take photos to monitor the coat color changes for your vet.
Is Coat Color Change Preventable?
Natural age-related coat color changes are not preventable in Shih Tzus. Gradual lightening of the coat over time is simply part of the aging process for some dogs.
However, you may be able to prevent or minimize certain stress or nutrition-related coat color changes by:
- Minimizing stressful situations when possible
- Ensuring your Shih Tzu’s diet is complete and balanced
- Having your vet run blood tests annually to check for deficiencies
- Starting supplements if any deficiencies are found
While you can’t change your Shih Tzu’s genetics, keeping their life low-stress and diet optimized gives your pup the best chance of maintaining a beautiful coat well into their senior years.
Is My Dog’s Coat Change Reversible?
It depends on the underlying cause:
- Age-related lightening – Not reversible
- Vitiligo – Permanent depigmentation, not reversible
- Cushing’s disease – Coat may re-darken if treated, but lightening can recur
- Hypothyroidism – Coat should re-darken once treated and regulated
- Nutrient deficiencies – Usually reversible with supplementation
- Skin infections – Coat should return to normal after treatment
- Stress – Reversible once the stressor is resolved
The key is having your vet accurately diagnose the root cause. Then you’ll know what to expect regarding reversing or managing the coat color change.
Should I Dye My Dog’s Coat?
You may be tempted to use pet hair dye to camouflage your Shih Tzu’s coat lightening or patchy hair loss. However, this is not recommended for a few reasons:
- Dyes contain harsh chemicals that may irritate your dog’s skin when left on for the required period.
- Accidentally ingesting the dye from licking their coats can make dogs sick.
- The dye can wash out unevenly, leaving splotchy or tie-dyed fur.
- Any skin conditions need to be diagnosed and won’t be cured by covering up the symptoms with dye.
- Skin must be extremely clean and free of oils for the dye to absorb properly.
- Dyes must be reapplied regularly as hair grows out.
Instead of dyeing their fur, focus your efforts on maintaining skin health and getting to the root cause of coat changes through veterinary care. Temporary whitening of the coat doesn’t affect your dog’s health or happiness.