Metformin is a widely used anti-hyperglycemic agent with weight loss effect properties but besides its various utilities, despite being very rare, it has its characteristic toxicity and adverse effects when used in large doses and for the long-term or in patients with renal impairment. We presented here a case of a 36-year-old woman who developed several presentations with diverse features during three years comprising neuropathic symptoms, severe lactic acidosis, three episodes of cardiogenic shock, acute kidney injury, megaloblastic anemia, pancytopenia, and hyponatremia and did not receive a definite diagnosis after each presentation until when she inadvertently disclosed her abuse of extremely unusual doses of metformin during these three years with aim of weight reduction obsessively without knowing that her symptoms could pertain to metformin overdose. She was eventually diagnosed with a body dysmorphic disorder which led to unreasonable abuse of metformin pills that consequently caused its toxicity. Thereafter, with cease of metformin use and psychiatric treatment, her symptoms did not recur and she was doing well after one year of her last admission. Based on the review of the literature, this is the first case of metformin toxicity in a patient with body dysmorphic disorder who was affected with extremely rare features of this intoxication, nevertheless, every manifestation of the patient was discussed exhaustively according to the current and available medical literature.