1. Rapid heartbeat or heart palpitations
A rapid heartbeat, also called tachycardia, is one of the most common symptoms of subclinical hyperthyroidism. It can cause you to feel anxious and out of breath. If you have a heart condition, this symptom can be dangerous.
2. Tremors, typically in your hands or fingers
Tremors are another common symptom of subclinical hyperthyroidism. They can affect your whole body, but they're most often felt in your hands or fingers.
3. Sweating or intolerance to heat
People with subclinical hyperthyroidism often sweat more than usual, even when they're not exercising or in a hot environment. They may also have trouble tolerating heat well.
4. Nervousness, anxiety, or feeling irritable
An overactive thyroid can cause mood changes, such as feeling nervous, anxious, or irritable. These feelings can be mild or severe.
5. Weight loss
Weight loss is a common symptom of subclinical hyperthyroidism. This weight loss is usually unintentional and can occur even if you're eating the same amount of food as usual.
6. Difficulty concentrating
An overactive thyroid can make it difficult to concentrate or focus on tasks. You may find yourself forgetting things more often than usual.
Fatigue is a common symptom of subclinical hyperthyroidism. You may feel tired all the time, even if you're getting enough sleep.
8. Muscle weakness
Muscle weakness is another common symptom of subclinical hyperthyroidism. This symptom can make it difficult to do your usual activities.
9. Skin changes, such as thinning or yellowing skin
Skin changes, such as thinning or yellowing skin, are another common symptom of subclinical hyperthyroidism.
10. Enlarged thyroid gland (goiter)
An enlarged thyroid gland, also called a goiter, is often a sign of subclinical hyperthyroidism. This symptom can cause the front of your neck to appear swollen.