User:Mr. Ibrahem/Acute radiation syndrome

Acute radiation syndrome (ARS), also known as radiation sickness or radiation poisoning, is a collection of health effects due to exposure to high amounts of ionizing radiation over a short period of time. Symptoms can begin within an hour and may last for several months. Symptoms within the first few days typically include nausea, vomiting, and loss of appetite. This is followed by a few hours or weeks with little symptoms which later develops into additional symptoms followed by either recovery or death.

Acute radiation syndrome involves a total dose of greater than 0.7 Gy (70 rads), that generally occurs from a source outside the body within minutes. Sources of such radiation can occur accidentally or intentionally. They may involve nuclear reactors, cyclotrons, and certain devices used in cancer therapy. It is generally divided into three types; bone marrow, gastrointestinal, and neurovascular syndrome, with bone marrow syndrome occurring at 0.7 to 10 Gy, and neurovascular syndrome occurring at doses that exceed 50 Gy. The cells that are most affected are generally those that are rapidly dividing. At high doses, this causes DNA damage that may be irreparable. Diagnosis is based on a history of exposure and symptoms. Repeated complete blood counts (CBCs) can indicate the severity of exposure.

Treatment of acute radiation syndrome is generally supportive care. This may include blood transfusions, antibiotics, colony-stimulating factors, or stem cell transplant. If radioactive material remains on the skin or in the stomach it should be removed. If radioiodine was breathed in or ingested, potassium iodide may be recommended. Complications such as leukemia and other cancers among those who survive are managed as usual. Short term outcomes depend on the exposure dose.

ARS is generally rare. A single event, however, can affect a relatively large number of people. Notable cases occurred following the atomic bombing of Hiroshima and Nagasaki and the Chernobyl nuclear power plant disaster. ARS differs from chronic radiation syndrome, which occurs following prolonged exposures to relatively low doses of radiation. In 2023 the World Health Organization updated its list of medicines for radiological and nuclear emergencies.