Self-harm behavior is the act of damaging intentionally one’s own body or a part of the body without suicidal intent. Severe self-injurious behavior is usually a manifestation of serious psychiatric disorders and may result in loss of an organ and/or organ function. Self-mutilation usually has irregular and repetitive characteristics. Medication misuse may lead to organ damage and failure. In this case, we present a psychotic patient acted in accordance with his delusions and developed renal failure after several self-injections of vitamin D, for a long time. A 38 years old, single, unoccupied, male patient was evaluated at nephrology service while treated due to acute renal failure. His first complaints were irritability, restlessness, increased in religious involvement, aggressive behaviors when he was a student in university. He thought his complaints were result from his weakness and began to inject vitamin D3 and other vitamin supplements to his body. He had been hospitalized four times at psychiatry clinics, when his symptoms get worse. He had been injecting vitamin D, vitamin B12, and vitamin C preparations for ten years from his shoulders and hips during this period; he had no complaints except for recurrent bizarre behavior. He did not use any psychiatric medication or treatment for the last 7 years. He had timidity, declined self-care, insomnia, loss of appetite and ulcers in his hips for last three months. He came in emergency clinic with these complaints under the custody of his family. He has been admitted with diagnosis of acute renal failure to internal medicine service. After improvement of metabolic conditions, he was transferred to our psychiatry clinic. In psychiatric examination, his self-care was insufficient, had somatic delusion of weakness of his body and delusion of medication himself with vitamin injections. In clinical follow-up, treatment of haloperidol 10 mg/day was continued that started in nephrology service. After partial remission in his psychotic symptoms, he was discharged. He did not attend to psychiatry outpatient clinic controls. Eighteen months later; his complaints such as weakness, fatigue, moodiness were increased and he was admitted to emergency service again. Blood creatinine level was found 7.8 in biochemical tests. He was hospitalized in nephrology service upon detection of chronic renal failure and he went under a hemodialysis program. Iatrogenic hypercalcaemia most frequently induced by inconvenient use of vitamin D. The main symptoms of vitamin D3 intoxication occur due to increased absorption of calcium from gastrointestinal tract causing to hypercalcaemia. Calcium has many effects on nerves, heart, muscles, digestive system and kidney. In hypercalcaemia fatigue, nausea, vomiting, polydipsia, polyuria, dehydration, loss of consciousness, hypercalciuria, nephrolithiasis, nephrocalcinosis, and renal failure can develop. It is discussed that self-mutilations in patients with psychotic disorders are usually formed as disrupting the integrity of the body. Differently from other similar cases, vitamin D3 injections had caused both metabolic and physical impairment at our patient’s body. In our case, repetitive injections of vitamin D3for about 12 years resulted in chronic renal failure.