This is a common condition of an abnormally low level of sugar in the blood. Sugar levels frequently change throughout the day and may be normal sometimes and abnormal at others. Symptoms include weakness, shakiness, excess hunger, anxiety, outbursts, faintness, headaches, passing out, delirium, coma, hallucinations, excess sweating, the appearance of intoxication, marked personality changes, irritability, negativism, mood swings, depression, crying spells, and a panorama of similar mental symptoms.
Numerous patients given psychiatric diagnoses have actually turned out to have hypoglycemia, including those classified with depression, manic-depressive disorder, and schizophrenia.
Questionnaire to help determine what ails you. From Blake Graham in Australia (PDF)