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Impaired Immune System

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Impaired Immune System

Impaired Immune System

The immune system is the body's natural defense system that helps fight infections. An impaired immune system does not work properly and can't effectively protect a person against infection.

Some conditions and medicines weaken or impair the immune system. These may include:

  • Substance use disorders or problems caused by quitting their use (withdrawal).
  • Certain diseases or conditions. Diabetes, cancer, HIV/AIDS, or conditions in which the body mistakenly identifies its own tissues as harmful (autoimmune disorders) are some examples.
  • Chemotherapy or radiation therapy.
  • Some medicines, such as corticosteroids or those taken to suppress the immune system after an organ transplant.
  • Surgery to remove the spleen (splenectomy).