Low levels of thyroid hormones, either caused by an underactive thyroid gland, or other disorders that affect circulating thyroid hormone levels (euthyroid sick syndrome) results in a range of symptoms that collectively indicate hypothyroidism. These symptoms may vary in intensity and in early stages of hypothyroidism, few or no symptoms may be present (subclinical hypothyroidism).
Signs and Symptoms of Hypothyroidism
The most characteristic signs and symptoms of hypothyroidism include :
- Fatigue. Severe tiredness and lethargy, after a little activity or for no apparent reason. This may also be experienced or interpreted as excessive sleepiness, diminished concentration, low energy levels or general ‘weakness’.
- Weight gain. The degree of weight gain may differ among individuals but it is usually a modest weight gain. This means that a person with a normal or healthy BMI (body mass index) will not gain weight to the degree that they will shift into the ‘obese’ category. Rather they may shift to the upper range of a healthy BMI or even fall into the overweight category.
- Sensitivity to cold. There is a noticeable intolerance to cold but should be differentiated from normal sensitivity to low temperatures. When related to hypothyroidism, the sensitivity to cold usually refers to an intolerance of low temperatures which were previously not a cause of discomfort.
In most cases, the presence or persistence of even one of these symptoms may warrant diagnostic investigation for low thyroid levels.
Other signs and symptoms, which may also be present, should not be immediately attributed to hypothyroidism, unless other possible causes have been excluded or if the one or more of the above symptoms are also present. These signs and symptoms may include :
- Dry skin and/or dry, coarse (rough) hair.
- Weak or brittle hair and nails.
- Goiter – enlargement of the thyroid gland which is more common in Hashimoto’s thyroiditis.
- Menstrual changes – particularly menorrhagia, which is prolonged and/or heavy periods.
- High blood cholesterol levels.
- Intellectual impairment, such as difficulty concentrating, forgetfulness or poor memory, difficulty in completing certain mental tasks or may even present as personality changes.
- Pale skin
- Muscle aches
- Joint pains
- Leg swelling
- Puffy face
- Droopy eyelids
- Puffiness or swelling around the eyes
- Dull facial expression
- Hoarse voice
- Slow speech
- Macroglossia – enlargement of the tongue.
- Hypothermia – low body temperature.
- Vitamin B12 deficiency
- Carotenemia – orange discoloration of the skin.
- Bradycardia – heart rate under 60 beats per minute.
- Abnormal reflexes
- Psychosis known as ‘myxedema madness’.
- Pleural effusion – fluid or ‘water’ around the lung.
- Abdominal effusion – fluid or ‘water’ in the abdominal cavity.
- Numbness or tingling of the hands and feet (paresthesia).
Myxedema is the medical term for severe hypothyroidism resulting in number of serious symptoms caused by the severity of the low thyroid hormone levels as well as the prolonged state of hypothyroidism. This state usually occurs in case of undetected, misdiagnosed or a poorly managed case of hypothyroidism.
Myxedema coma is a life-threatening complication of severe hypothyroidism and is triggered by exposure to cold, trauma, infection or drugs that suppress the central nervous system (like ‘sleeping tablets’, anesthetics or in alcohol abuse). Characteristic features of myxedema coma is a coma with hypothermia (low body temperature), depressed or absent reflexes (areflexia), shallow breathing, hypoxia, seizures and reduced blood flow to the brain. Immediate medical treatment is required or death may occur.