Situated at the front of the neck, the thyroid gland is shaped like a butterfly. It belongs to the endocrine (glandular) system and helps regulate the supply of hormones to the body. Hormones orchestrate the various functions of the organs. Hypothyroidism occurs when the thyroid produces an insufficient amount of hormone. According to "Current Medical Diagnosis and Treatment" and "Harrison's Manual of Medicine," the symptoms can range from mild to severe. Not all symptoms have to be present for the diagnosis but generally a few are present simultaneously.
Speech
Constant demand to produce thyroid hormone causes the thyroid gland to enlarge. It then takes up more than its allotted space, infringing on the tissue around it. This causes a deep, hoarse voice and difficulty swallowing. Speech slows and slurs as the tongue thickens.
Neurological
Neurological symptoms include numb and tingly extremities and an intolerance to cold temperatures. Carpal tunnel syndrome, common in people with hypothyroidism, causes burning in the fingers. This is more noticeable during the night, when the hands relax into positions that impinge the radial nerve in the wrist. The acuity of taste, smell and hearing diminishes. Headaches occur in succession with varying intensity.
Heart and Lungs
Low levels of thyroid hormone cause a slower heart rate and drop in blood pressure. Because it is working harder, the heart's walls thicken, making it less efficient. If fluid gathers in the lungs, simple tasks may bring on shortness of breath. Tiredness sets in with the slightest exertion. The body retains fluid in the extremities, face and eyelids.
Muscles and Joints
Muscles weaken and become tender and stiff or cramp painfully. Fluid leaks into joints, causing localized pain. Less commonly, the neck feels painful or stiff with limited range of motion.
Constipation and Weight Gain
An underactive thyroid slows down bowel function, leading to constipation. Although appetite wanes, weight increases due to a slower metabolism and fluid retention.
Skin and Hair
Hypothyroidism causes thinning hair on the body and head. A classic symptom is the loss of hair at the outer edge of the eyebrows. Nails crack and peel as they become dry and brittle. The skin dries out, causing itching and flaking, and may take on a yellow tone.
Mental Health
Depression appears or becomes worse. Lethargy and fatigue make it hard to function on a daily basis. Psychosis occurs in extreme cases. Forgetfulness is common.
Menstrual
Women may have irregular periods or a very heavy menstrual flow.
References
- "Current Medical Diagnosis and Treatment"; Stephen J. McPhee and Maxine A. Papadakis; 2010
- "Harrison's Manual of Medicine"; Anthony S. Fauci et al; 2009
