Thyroid stimulating hormone, usually abbreviated TSH, is manufactured by the pituitary gland. Release of TSH stimulates the thyroid to make T3 and T4, the hormones responsible for thyroid function. If the thyroid stops functioning, TSH levels rise as the body attempts to "force" the thyroid to produce hormones. This reaction, known as a feedback loop, causes TSH levels to rise above their normal range. High blood levels of TSH indicate an underactive thyroid, or hypothyroid, a condition that affects as many as 10 percent of women and six percent of men older than age 65 years, the Merck Manual states, and causes a variety of symptoms.

  Advertisement
 
Integumentary Symptoms

High TSH levels due to underactive thyroid causes many changes in the skin and hair. Skin often becomes dry, scaly, thick and pale. Palms and soles of the feel may appear yellowish due to the deposit of carotene. Hair thins and turns dry and coarse. Fluid retention and weight gain may occur, along with puffiness of the face and swelling around the eyes. The facial expression may appear dull; eyelids may droop. Nails become brittle and break easily. The tongue may be enlarged.

  Advertisement
 
  Video of the Day
  
Mental Changes

People with elevated TSH often experience mental changes. They may become depressed, suffer memory loss, and have difficulty processing information. Speech may be slow and dementia may occur. If TSH hormone levels are extremely low for long periods of time a life-threatening condition called myxedema coma may occur.

Musculoskeletal Symptoms

High TSH levels from thyroid disease lead to muscle and joint aches and pains, along with stiffness and swelling. Weakness and loss of deep tendon reflexes may occur. Numbness and tingling in the extremities commonly occur.

  Advertisement
 
Systemic Symptoms

Systemic symptoms of high TSH from underactive thyroid include cold sensitivity due to a low body temperature, sluggishness and fatigue. If myxedema coma develops, seizures and coma can occur.

  Advertisement
 
Cardiopulmonary Symptoms

Elevated TSH levels from low-functioning thyroid can cause cholesterol levels to rise. Heart enlargement and heart failure can occur even in people with subclinical thyroid disease, which has few symptoms, the Mayo Clinic warns. Fluid can build up around the heart and lungs and the heart rate may become bradycardic, or slower than normal.

  Advertisement
 
Gynecological Symptoms

Women with high TSH levels may have heavier than normal periods or no periods at all. Infertility can occur due to a lack of ovulation. Sex drive often decreases.

  Advertisement
 
  Advertisement
  
  references
  
      Merck Manual: Hypothyroidism
    
      MayoClinic.com: Hypothyroidism
    
      endocrineweb: Hypothyroidism
    
      endocrineweb: How Your Thyroid Works
     Is this an emergency?
If you are experiencing serious medical symptoms, please see the
National Library of Medicine’s list
of signs you need emergency medical attention or call 911.





  references
  
      Merck Manual: Hypothyroidism
    
      MayoClinic.com: Hypothyroidism
    
      endocrineweb: Hypothyroidism
    
      endocrineweb: How Your Thyroid Works

Is this an emergency? If you are experiencing serious medical symptoms, please see the National Library of Medicine’s list of signs you need emergency medical attention or call 911.

      Merck Manual: Hypothyroidism
    
      MayoClinic.com: Hypothyroidism
    
      endocrineweb: Hypothyroidism
    
      endocrineweb: How Your Thyroid Works