What are the Risks for and Symptoms of Hyperthyroidism?

by Mary Shomon Patient Advocate

Your thyroid is a small, butterfly-shaped gland, but it packs a punch in terms of the many symptoms it can cause when it isn’t working properly. The thyroid gland produces essential hormones that help oxygen and energy reach every cell, tissue, gland, and organ in your body. When your thyroid is overactive, you have too much thyroid hormone — a condition known as hyperthyroidism—and your body can feel like it’s in overdrive.

Risk factors for hyperthyroidism

There are a number of factors that put you at greater risk of hyperthyroidism. These include:

  • A personal or family history of thyroid disease

  • A personal or family history of autoimmune disease

  • Pregnancy or childbirth within the last year

  • Extreme physical or life stress

  • Excessive exposure to iodine

  • Cigarette smoking

In addition, there are a number of conditions that either increase your risk for or may be a result of hyperthyroidism. These include:

  • Infertility - Recurrent miscarriage or pregnancy - Autoimmune diseases, including alopecia, vitiligo, Sjogren’s syndrome, multiple sclerosis, psoriasis, rheumatoid arthritis, type 1 diabetes, pernicious anemia, and many others

Symptoms of hyperthyroidism

According to the 2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism, the symptoms of hyperthyroidism usually reflect a speeding up of your key bodily functions. Everything from emotional reactions and digestion to heart rate can be affected, as evident by the following list of common symptoms.


  • Fatigue and exhaustion, unrelieved by sleep


  • Insomnia

  • Difficulty falling asleep or staying asleep

  • Early waking

Weight, Appetite, Thirst

  • Weight loss, despite no change to diet or exercise, or even with an increase in caloric intake

  • An inability to gain weight, even after adding calories

  • Unrelieved hunger

  • Excessive thirst

  • An unusually low blood sugar level or Hemoglobin A1C (HA1C) level

Mood and cognition

  • Anxiety and nervousness

  • Panic attacks

  • Anger and irritability

  • Easy startling

  • Hyperactivity, excessive fidgeting, and/or temper tantrums in children and adolescents

Neck and thyroid area

  • A swollen or full feeling in your neck

  • A visible enlargement of your neck

  • A visible lump in your neck

  • A lump in your neck that you can’t see but can feel

  • Discomfort with things around your neck, such as scarves, ties, or turtleneck

  • Difficulty or discomfort swallowing

  • Neck tenderness

  • A sore throat

  • A raspy, hoarse voice


  • Hair loss from your head or body

  • Hair that is thinner or finer than usual


  • Fingernails that split or break easily

  • Thickening of the fingernail area, known as acropachy


  • Patches of skin rash on the legs - A fine, reddish rash on the face (milaria bumps) - Unusually smooth skin texture - Hives (urticaria)

Digestion and elimination

  • Chronic diarrhea or loose stools

Menstrual period

  • Lighter menstrual periods

  • Less frequent menstrual periods

  • Cessation of menstrual periods

Pregnancy and postpartum

  • Weight loss during pregnancy

  • Excessive nausea and/or vomiting in pregnancy

  • Rapid weight loss after pregnancy

  • Postpartum depression and/or anxiety

Body, muscles, and joints

  • Unusually fast and hyperresponsive reflexes

  • Tremors, especially in the hands

  • Muscle and joint aches and pains

  • Pain and weakness in the upper arms and legs

Heart and blood pressure

  • Unusually fast heart rate

  • Unusually high blood pressure

  • Heart palpitations and arrhythmias


  • Unusually low cholesterol levels


  • A dry, gritty feeling in your eyes

  • Light sensitivity

  • Bulging eyes

  • Double vision


  • A low-grade fever

  • Feeling hot, especially when others feel cold, or feeling hot in cold rooms and climates

  • Excessive sweating

Note that you don’t need to have all of the listed symptoms or even many of them. Experiencing just a few of these symptoms may point to undiagnosed hyperthyroidism, or may indicate that your hyperthyroidism warrants better and more effective treatment.

A note about thyroid storm: A small percentage of people with hyperthyroidism develop a dangerous condition known as thyroid storm The symptoms of thyroid storm include:

  • a very high fever, often more than 105 degrees

  • a heart rate that can be as high as 200

  • heart palpitations

  • pain in the chest

  • difficulty breathing

  • severely elevated blood pressure

  • confusion

Thyroid storm is life-threatening and requires immediate emergency medical attention to avoid stroke or heart attack.

Mary Shomon
Meet Our Writer
Mary Shomon

Mary Shomon is a patient advocate and New York Times bestselling author who empowers readers with information on thyroid and autoimmune disease, diabetes, weight loss and hormonal health from an integrative perspective. Mary has been a leading force advocating for more effective, patient-centered hormonal healthcare. Mary also co-stars in PBS’ Healthy Hormones TV series. Mary also serves on HealthCentral’s Health Advocates Advisory Board.