Hypothyroidism
Too much Thyroid Hormone triggers an assortment of physical and mental changes in the cat. Hyperthyroidism is most commonly seen in older cats and causes cardiac abnormalities, agitation, hyperactivity and marked weight loss. Any older cat with a rapid heart rate, weight loss accompanied by a good appetite, and slight hyperactivity should be checked for hyperthyroidism. Treatment can vary depending upon the actual cause but this disorder is generally well controlled once diagnosed.