Many deficiencies and disorders can damage or disrupt your immune system. Some medicines make it harder for your body to fight infection. Certain health conditions cause your immune system to attack healthy cells or make it hard for your immune system to protect you from harmful germs. They include:
- Allergies: When the body overreacts to a harmless substance (such as food or pollen), the immune system launches a response. Your body fights its allergy triggers by releasing histamines that cause allergy symptoms. An allergic reaction can range from mild (sneezing or stuffy nose) to severe (breathing problems and even death). Antihistamine medications help calm the symptoms.
- Autoimmune disorders: These disorders occur when the immune system mistakenly attacks its own healthy cells. Lupus, diabetes, Hashimoto’s disease and rheumatoid arthritis are examples of common autoimmune diseases.
- Primary immunodeficiency disorders: These disorders are inherited (passed along in families). There are more than 100 primary immunodeficiency diseases (PIDD) that prevent the immune system from working as it should.
- Infections: HIV and mononucleosis (mono) are well-known infections that weaken the immune system. They lead to serious illness.
- Cancer: Certain types of cancer, like leukemia, lymphoma and myeloma affect the immune system directly. These cancers occur when immune cells grow uncontrollably.
- Sepsis: Sepsis is an overwhelming response of your body’s immune system to an infection. This triggers widespread inflammation and causes a downward spiral of events that can end in organ damage, organ failure and death.
- Medications: Some medications, such as corticosteroids, can weaken the immune system. And after an organ transplant, people take immunosuppressant medications. These medicines help prevent a failed transplant (rejection). However, these drugs increase your risk of infection and disease.