Graves’ disease is by far the more dangerous of these two autoimmune thyroid disorders. Overproduction of thyroid hormones can lead to thyrotoxicosis, a condition associated with excess thyroid hormones. Thyrotoxicosis is a medical emergency, causing rapid heart rate, abnormal heart rhythms, shortness of breath, insomnia, coma and ultimately death if not treated.[1]
In contrast, although hypothyroidism associated with Hashimoto’s disease produces a number of unpleasant symptoms, these are not generally life-threatening and can be managed with normalization of thyroid hormones through thyroid hormone replacement therapy. Both Graves’ disease and Hashimoto’s disease are risk factors for other autoimmune diseases.[2]