I take 75mcg of levothyroxine daily for hypothyroidism (hashimoto's) and a goitre. what would happen if i stopped taking my medication?

Nothing good: B"sd Most likely you would become hypothyroid, which often causes symptoms including fatigue, cognitive decline (especially for math) and signs ranging from mild - dry skin, constipation - to life threatening - myxedema coma. Goitre is also likely to grow larger and could even cause compressive symptoms such as difficulty swallowing and breathing and hoarseness. Glad to discuss in more detail.