From the Guidelines
Hypothyroidism symptoms include fatigue, feeling cold, weight gain, hair loss, and constipation, which can be subtle and nonspecific, making them easy to attribute to other conditions 1. These symptoms occur because the thyroid gland doesn't produce enough thyroid hormones, which are essential for regulating metabolism. When metabolism slows, many bodily functions slow down as well.
- Symptoms typically develop gradually over years and may be subtle at first, making them easy to attribute to aging or other conditions.
- The severity of symptoms correlates with the degree of thyroid hormone deficiency.
- Elderly patients might present with fewer symptoms, sometimes only showing cognitive decline or fatigue.
- If you experience multiple symptoms, especially persistent fatigue, weight gain despite not changing diet or exercise habits, or increased cold sensitivity, consult a healthcare provider for thyroid function testing, which involves a simple blood test measuring thyroid-stimulating hormone (TSH) and sometimes free T4 levels. It's worth noting that some individuals with subclinical hypothyroidism, characterized by TSH levels between 4.5 and 10 mIU/L, may also experience symptoms compatible with hypothyroidism, and a trial of levothyroxine may be considered while monitoring for improvement in hypothyroid-type symptoms 2.
From the FDA Drug Label
The clinical features of myxedema coma include depression of the cardiovascular, respiratory, gastrointestinal and central nervous systems, impaired diuresis, and hypothermia. The symptoms of hypothyroidism (underactive thyroid) include:
- Depression of the cardiovascular system
- Depression of the respiratory system
- Depression of the gastrointestinal system
- Depression of the central nervous systems
- Impaired diuresis
- Hypothermia 3
From the Research
Symptoms of Hypothyroidism
The symptoms of hypothyroidism can vary and may be nonspecific, especially in the early stages of the disease. Some common symptoms include:
- Fatigue and lethargy 4, 5, 6, 7, 8
- Cold intolerance 4, 5, 6, 7, 8
- Weight gain 5, 6, 7, 8
- Constipation 4, 5, 6, 7
- Dry skin 5, 6, 7, 8
- Change in voice 5, 6, 7, 8
- Hair loss 6, 8
- Depression 8
- Irregular menses 8
- Bradycardia 4, 8
- Myalgias 8
- Hyperlipidemia 8
Subclinical Hypothyroidism
In subclinical hypothyroidism, symptoms may be absent or minimal 4, 5. The diagnosis of subclinical hypothyroidism is based on elevated thyroid-stimulating hormone (TSH) levels with normal serum free thyroxine (fT4) and triiodothyronine (fT3) levels 4.
Severity of Symptoms
The severity of symptoms can vary depending on the age, sex, and severity of the condition 6, 7. In some cases, hypothyroidism can lead to life-threatening complications, such as myxedema coma 5, 7.