Some people with hyperthyroidism have no symptoms. When they do occur, symptoms can include:
- Anxiety, irritability, or trouble sleeping
- Weakness (especially in the arms and thighs, which can make it hard to lift heavy things or climb stairs)
- Sweating a lot and having trouble dealing with hot weather
- Fast or uneven heartbeats
- Feeling tired
- Weight loss even when you are eating normally
- Frequent bowel movements
Hyperthyroidism can also cause a swelling in the neck called a “goiter.” If it is caused by a medical problem called Graves’ disease, the condition can also make the eyes bulge.
Untreated hyperthyroidism can cause a heart rhythm disorder called “atrial fibrillation,” chest pain, and rarely, heart failure.
In women, hyperthyroidism can disrupt monthly periods. It can also make it hard to get pregnant.
In men, hyperthyroidism can cause the breasts to grow or lead to sexual problems. These problems go away when hyperthyroidism is treated.