Cytokine receptor antagonists are a class of medications that block the action of cytokines, which are proteins involved in cell signaling and immune responses. By inhibiting these receptors, these drugs can reduce inflammation and modulate the immune system, making them useful in treating various autoimmune diseases and inflammatory conditions. Commonly used in conditions like rheumatoid arthritis and inflammatory bowel disease, cytokine receptor antagonists help alleviate symptoms and improve quality of life. Examples include tocilizumab, which targets the interleukin-6 receptor, and anakinra, which blocks the interleukin-1 receptor. These therapies represent a significant advancement in managing chronic inflammatory diseases.