Radiation syndrome

Acute radiation syndrome is a life-threatening illness in which a high dose of ionizing radiation received over a short period damages rapidly dividing tissues across several organ systems. It is rare, and exposure at this level is usually tied to major safety failures rather than routine medical imaging or treatment. Causes include nuclear accidents or detonations, contamination with radioactive material, and accidental overexposure during medical or industrial work. Presentation often begins with nausea and vomiting, followed by weakness, fever, diarrhoea, hair loss, skin burns and bleeding. Bone marrow, gut and skin are the most vulnerable tissues. Assessment relies on exposure history, the timing of symptoms and repeated blood counts, with falling lymphocyte counts the best guide to exposure. Care centres on decontamination and supportive treatment, including fluids, antiemetics, pain relief and early antibiotics, with colony-stimulating factors for marrow suppression and, in selected cases, stem cell transplantation.

Seek urgent care for severe symptoms that come on suddenly, for difficulty breathing, or for drowsiness or confusion. See a doctor when symptoms persist, keep coming back, or affect daily life. Call the local emergency number for any symptom that is sudden and severe. This page is a reference for healthcare professionals and does not replace an assessment.