Boric acid is toxic to humans and is a dangerous chemical that can cause some irritation to the skin, digestive tract, and nervous system. 1. Skin irritation: under normal circumstances, boric acid does not cause much harm to the human body, but if too much boric acid, may make the skin exfoliative dermatitis, localized rash. 2. Digestive tract stimulation: Boric acid can also cause acute poisoning, oral mucosa, esophageal mucosa damage, nausea and vomiting, abdominal pain, diarrhea, irritation, and in severe cases, even fever, dehydration, renal failure, coma and other situations. 3. Neurological stimulation: some patients using boric acid will have dizziness and headache, blurred consciousness and other symptoms, the more serious may also appear ataxia, mental confusion and other manifestations, and even symptoms of neurological dysfunction such as meningeal irritation sign. If patients experience physical discomfort after exposure to boric acid, they should go to the hospital in time and deal with treatment under the guidance of a doctor to avoid delaying their condition.