Pyridine is harmful if inhaled, swallowed or absorbed through the skin. Effects of acute pyridine intoxication include dizziness, headache, lack of coordination, nausea, salivation, and loss of appetite. They may progress into abdominal pain, pulmonary congestion and unconsciousness. One person died after accidental ingestion of half a cup of pyridine. The lowest known lethal dose (LDLo) for the ingestion of pyridine in humans is 500 mg·kg−1. In high doses, pyridine has a narcotic effect and its vapor concentrations of above 3600 ppm pose a health risk. The oral LD50 in rats is 891 mg·kg−1. Pyridine is flammable.