A 29 year old woman comes to the clinic because of 6 months of amenorrhea and intermittent milky nipple discharge. She takes risperidone for schizophrenia. Pregnancy test is negative. Physical examination is otherwise normal, and MRI of the sella is unremarkable. Which of the following best explains this patient's symptoms?
- A)Autonomous ACTH secretion from corticotrophs
- B)Increased hypothalamic GnRH secretion
- C)Decreased hypothalamic dopamine signaling to lactotrophsGABARITO
- D)Autoantibodies stimulating the TSH receptor
- E)Increased posterior pituitary oxytocin release
Explicação
Risperidone blocks dopamine D2 receptors. Dopamine normally inhibits prolactin release from anterior pituitary lactotrophs, so loss of dopaminergic inhibition causes hyperprolactinemia with galactorrhea and amenorrhea from suppression of GnRH. The normal sella... Ver explicação completa e trilha adaptativa →