<Li> Neurovascular . This syndrome typically occurs at absorbed doses greater than 30 Gy (3000 rad), though it may occur at 10 Gy (1000 rad). It presents with neurological symptoms such as dizziness, headache, or decreased level of consciousness, occurring within minutes to a few hours, and with an absence of vomiting . It is invariably fatal . </Li> <P> The prodrome (early symptoms) of ARS typically includes nausea and vomiting, headaches, fatigue, fever, and a short period of skin reddening . These symptoms may occur at radiation doses as low as 0.35 Gy (35 rad). These symptoms are common to many illnesses, and may not, by themselves, indicate acute radiation sickness . </P> <Table> <Tr> <Th> Phase </Th> <Th> Symptom </Th> <Th_colspan="5"> Whole - body absorbed dose (Gy) </Th> </Tr> <Tr> <Th> 1--2 Gy </Th> <Th> 2--6 Gy </Th> <Th> 6--8 Gy </Th> <Th> 8--30 Gy </Th> <Th>> 30 Gy </Th> </Tr> <Tr> <Td> Immediate </Td> <Td> Nausea and vomiting </Td> <Td> 5--50% </Td> <Td> 50--100% </Td> <Td> 75--100% </Td> <Td> 90--100% </Td> <Td> 100% </Td> </Tr> <Tr> <Td> Time of onset </Td> <Td> 2--6 h </Td> <Td> 1--2 h </Td> <Td> 10--60 min </Td> <Td> <10 min </Td> <Td> Minutes </Td> </Tr> <Tr> <Td> Duration </Td> <Td> <24 h </Td> <Td> 24--48 h </Td> <Td> <48 h </Td> <Td> <48 h </Td> <Td> N / A (patients die in <48 h) </Td> </Tr> <Tr> <Td> Diarrhea </Td> <Td> None </Td> <Td> None to mild (<10%) </Td> <Td> Heavy (> 10%) </Td> <Td> Heavy (> 95%) </Td> <Td> Heavy (100%) </Td> </Tr> <Tr> <Td> Time of onset </Td> <Td>--</Td> <Td> 3--8 h </Td> <Td> 1--3 h </Td> <Td> <1 h </Td> <Td> <1 h </Td> </Tr> <Tr> <Td> Headache </Td> <Td> Slight </Td> <Td> Mild to moderate (50%) </Td> <Td> Moderate (80%) </Td> <Td> Severe (80--90%) </Td> <Td> Severe (100%) </Td> </Tr> <Tr> <Td> Time of onset </Td> <Td>--</Td> <Td> 4--24 h </Td> <Td> 3--4 h </Td> <Td> 1--2 h </Td> <Td> <1 h </Td> </Tr> <Tr> <Td> Fever </Td> <Td> None </Td> <Td> Moderate increase (10--100%) </Td> <Td> Moderate to severe (100%) </Td> <Td> Severe (100%) </Td> <Td> Severe (100%) </Td> </Tr> <Tr> <Td> Time of onset </Td> <Td>--</Td> <Td> 1--3 h </Td> <Td> <1 h </Td> <Td> <1 h </Td> <Td> <1 h </Td> </Tr> <Tr> <Td> CNS function </Td> <Td> No impairment </Td> <Td> Cognitive impairment 6--20 h </Td> <Td> Cognitive impairment> 24 h </Td> <Td> Rapid incapacitation </Td> <Td> Seizures, tremor, ataxia, lethargy </Td> </Tr> <Tr> <Td> Latent period </Td> <Td> </Td> <Td> 28--31 days </Td> <Td> 7--28 days </Td> <Td> <7 days </Td> <Td> None </Td> <Td> None </Td> </Tr> <Tr> <Td> Illness </Td> <Td> </Td> <Td> Mild to moderate Leukopenia Fatigue Weakness </Td> <Td> Moderate to severe Leukopenia Purpura Hemorrhage Infections Alopecia after 3 Gy </Td> <Td> Severe leukopenia High fever Diarrhea Vomiting Dizziness and disorientation Hypotension Electrolyte disturbance </Td> <Td> Nausea Vomiting Severe diarrhea High fever Electrolyte disturbance Shock </Td> <Td> N / A (patients die in <48h) </Td> </Tr> <Tr> <Td> Mortality </Td> <Td> Without care </Td> <Td> 0--5% </Td> <Td> 5--95% </Td> <Td> 95--100% </Td> <Td> 100% </Td> <Td> 100% </Td> </Tr> <Tr> <Td> With care </Td> <Td> 0--5% </Td> <Td> 5--50% </Td> <Td> 50--100% </Td> <Td> 99--100% </Td> <Td> 100% </Td> </Tr> <Tr> <Td> Death </Td> <Td> 6--8 weeks </Td> <Td> 4--6 weeks </Td> <Td> 2--4 weeks </Td> <Td> 2 days--2 weeks </Td> <Td> 1--2 days </Td> </Tr> <Tr> <Td_colspan="7"> Table Source </Td> </Tr> </Table> <Tr> <Th> Phase </Th> <Th> Symptom </Th> <Th_colspan="5"> Whole - body absorbed dose (Gy) </Th> </Tr>

How long does it take to die from radiation poisoning
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