The onset of clinical signs of poisoning may be delayed several days after exposure to a single large dose or after a few weeks of repeated ingestion of small doses. Cardiopulmonary and neurologic signs and symptoms, common in rat poisonings, have not been reported in human cases. The principle diagnostic test in a demonstration of markedly reduced prothrombin activity in blood plasma, as measured by the method of Quick or one of its modifications. The test should be repeated at least twice daily until a normal prothrombin time is established. Also, the blood clotting time and the bleeding time should be obtained.
Blood is often demonstrable in the excreta.
If small amounts of the compound have been ingested by either an adult or a child and the victim is asymptomatic, treatment is probably unnecessary. If there is uncertainty about the dose or the general health of the victim, Vitamin K 1 may be given orally as a prophylactic treatment. Observe the patient for 4-5 days. If the dose is known to be large or the victim is showing signs of poisoning, induce vomiting with Syrup of Ipecac or perform a gastric lavage within 2-3 hours of ingestion. Follow with activated charcoal treatment to limit absorption of any toxicant remaining in the gastrointestinal tract.