The clinical symptoms of this disease are multisystemic i.e. it's a condition that affects many organ systems of the body and relates to increased or decreased metabolic rate.

Owners often overlook early symptoms or assume the changes are a normal part of the aging process. Obvious weight loss or gain are usually the problem that takes the dog to their veterinarian.

For hyperthyroidism other signs include rapid heart rate , muscle weakness, goiter (enlargement of the thyroid gland), irregular heart rhythm, hyperexcitability , increased appetite , increased thirst , increased urination. heat intolerance, and an unkempt hair coat.

My recommendations are to start your dog on a Thyroid Regulator (same as Human)
The herbs in this mix include:- Oats, Dandelion, Bladderack, Nettle, Blue Flag and Ginseng. To this mix I add the Bach Flower Remedies; for an overactive thyroid include Scleranthus, Impatiens,Cerato, Chestnut Bud and Pine, for an underactive Thryroid I add the Bach Flowers Wild Rose, Olive, Sweet Chestnut and Sclernathus.

It is recommended that you place your dog on a diet of raw meat, raw chicken necks and wings, definitely NO PROCESSED food and snacks. You can also add some freshly cooked vegetables and rice as well. Read the information available on this link.