MON-427 An Interesting Case of Drug-Induced Hyperprolactinemia in a Patient Who Presented with Psychosis

Background: Hyperprolactinemia is a condition characterized by excess prolactin concentration exceeding the upper limit of normal. Prolactin is a peptide hormone secreted solely by the lactotroph cells of the pituitary gland. Hyperprolactinemia may be caused by several physiological and pathological conditions most common of which is benign tumor of the pituitary gland. It is very important to differentiate this cause from other pathological causes of hyperprolactinemia. Medication use is a common cause of hyperprolactinemia. We present a case of hyperprolactinimia due to antipsychotic use in a patient who presented with psychosis. Clinical case: We present a case of a 67 Y/O female who presented to our hospital from a nursing home with altered mental status. Her medical history was remarkable for hypertension, paranoid schizophrenia and ESRD on dialysis. She was admitted to the hospital for further evaluation and was noted to have bilateral mastoiditis and acute exacerbation of paranoid schizophrenia. In view of altered mental status TSH was checked which was low and she was noted to have elevated Free T4. Endocrinology was consulted for hyperthyroidism. She was started on methimazole for hyperthyroidism. Also patient was noted to have elevated prolactin level with level as high as 729 ng/ml on admission. In view of hyperprolactinemia MRI brain was done which did not show any evidence of pituitary adenoma. On review of medications it was noted that patient was on perphenazine and olanzapine for paranoid schizophrenia. It was concluded that patients hyperprolactinemia was due to medications which included antipsychotics. Psychiatry was consulted and her antipsychotics were discontinued and she was started on antipsychotics which did not have any effect on prolactin level. After discontinuing the medication her prolactin level came down to 135 ng/ml on the day of discharge. Conclusion :This is an unusual presentation of drug induced hyperprolactinemia in patient on antipsychotics. Most of the drugs do not cause an elevation of prolactin level more than 100 ng/ml with antipsychotics causing elevation upto 300 or even 400 ng/ml. This patient did have a prolactin level of 729 ng/ml with negative MRI which is not very common.