Y43: Primarily systemic agents

Y43.4: Immunosuppressive agents

Immunosuppressive agents are a category of drugs used primarily in the management of autoimmune diseases or to prevent organ transplant rejection. This is because these drugs work by reducing or turning off the body's immune system, which can effectively control autoimmune conditions characterized by an overactive immune system. Similarly, in post-organ transplant scenarios, these drugs help prevent the immune system from treating the new organ as a foreign body and rejecting it. However, a significant side effect of taking immunosuppressive agents is an increased susceptibility to infections and certain types of cancer due to the dampening of the immune system. It is common for patients taking these drugs to experience symptoms such as fatigue, reduced appetite, and a heightened frequency of infections. The severity and type of the symptoms can vary substantially among individuals, depending on multiple factors including the specific drug being used, the dosage, and the patient's overall health condition.