Hyperprolactinemia In The Setting Of Risperidone Use and Delusions of Pregnancy

Risperidone, an atypical antipsychotic, is known to be the most likely of its class of medication to cause hyperprolactinemia. We present a case of a 33 year old female with no known psychiatric history with chief complaint of “I’m pregnant and my breasts hurt”. She presented with bizarre and disorganized behavior, sexual preoccupation and agitation. Serum pregnancy test and uterine ultrasound were negative. The patient was started on risperidone 1 mg BID for suspected schizophrenia. Though the patient’s mood and psychotic symptoms steadily improved, she continued to report breast fullness and pain. Medical record request from a nearby hospital revealed that two weeks prior to presentation, the patient was treated with risperidone 2 mg BID during an involuntary psychiatric admission. Thus, a prolactin level was ordered and found to be 62.0 ng/ml (ref range 5.2-26.5 ng/ml). Accordingly, risperidone was discontinued as the likely cause of symptomatic hyperprolactinemia and aripiprazole 5 mg daily was started. Upon discharge, the patient endorsed relief of breast pain and had improvement in thought organization and delusions (repeat prolactin level 40.9 ng/ml). This case highlights the careful clinical consideration needed for female patients who present with unspecified psychosis with delusions of pregnancy, as they may be experiencing symptoms (i.e. amenorrhea, breast fullness/pain) as known side effects of a common first-line atypical antipsychotic. Clinicians may consider ordering serum prolactin levels in these patients if no reliable collateral or medical information is available so as to not delay patient care.