Management of a microprolactinoma with aripiprazole in a woman with cabergoline-induced mania

The Effect of Antipsychotics on Prolactinoma Growth: A Radiological and Serological Analysis

Many antipsychotic (AP) medications work by reducing dopamine levels. As hyperdopaminergia is known to cause psychosis, antipsychotics work to relieve these symptoms by antagonizing dopamine receptors and lowering dopamine levels. Dopamine is also a known negative modulator of the prolactin pathway, which allows for drug agents like dopamine agonists (DAs) to be incredibly effective in managing tumors that secrete excess prolactin (prolactinomas). While the effects of DAs on prolactinoma size and growth have been studied for decades, the effects of APs on prolactinoma size remain to be seen. We hope to investigate the effects of APs on prolactinomas by conducting a thorough PubMed search, including patients with diagnosed prolactinoma on concurrent AP therapy. Our search led to 27 studies with a total of 32 patients. We identified themes regarding seven antipsychotics: risperidone, haloperidol, amisulpride, thioridazine, aripiprazole, olanzapine, and clozapine. Risperidone, haloperidol, amisulpride, and thioridazine caused a significant increase in prolactin in most cases where they were used, and prolactin decreased after their discontinuation. For example, risperidone discontinuation resulted in a decrease in prolactin levels by an average of 66%, while haloperidol, amisulpride, and thioridazine discontinuation lowered prolactin by an average of 82%, 72%, and 89.7%, respectively. However, there were some exceptions in regard to risperidone, haloperidol, and thioridazine, where prolactin levels were not as severely affected. Aripiprazole, olanzapine, and clozapine all had significant reductions in prolactin levels when patients were switched from another antipsychotic, such as risperidone or haloperidol. The average percent decrease in prolactin when switched to aripiprazole was 67.65%, while it was 54.16% and 68% for olanzapine and clozapine, respectively. The effect of individual antipsychotics on prolactinoma size was difficult to ascertain, as imaging was not obtained (or indicated) after every antipsychotic switch, and many patients were taking dopamine agonists concurrently. Therefore, it would be difficult to ascertain which factor affected size more. Also, some patients received surgery or radiotherapy, which completely negated our ability to make any assertions about the effects of certain pharmacological agents. Although it is difficult to ascertain the role that antipsychotic medications play in the formation of prolactinoma, we have found that the cessation of certain antipsychotic medications may lead to a reduction in prolactin levels and possibly the presence of a measurable prolactinoma.

Full Remission of Long-Term Premenstrual Dysphoric Disorder-Like Symptoms Following Resection of a Pituitary Adenoma: Case Report

Patient: Female, 44-year-old

Final Diagnosis: Pituitary adenoma

Symptoms: Depression and anxiety

Medication:—

Clinical Procedure: —

Specialty: Neurosurgery • Psychiatry

Neuropsychiatric and metabolic aspects of dopaminergic therapy: perspectives from an endocrinologist and a psychiatrist

The dopaminergic treatment represents the primary treatment in prolactinomas, which are the most common pituitary adenomas and account for about 40% of all pituitary tumours with an annual incidence of six to ten cases per million population. The dopaminergic treatment includes ergot and non-ergot derivatives with high affinity for the dopamine receptors D1 or/and D2. Through the activation of the dopaminergic pathway on pituitary lactotrophs, the dopamine agonists inhibit the prolactin synthesis and secretion, therefore normalizing the prolactin levels and restoring eugonadism, but they also lead to tumour shrinkage. Treatment with dopamine agonists has been associated - apart from the common side effects such as gastrointestinal symptoms, dizziness and hypotension - with neuropsychiatric side effects such as impulse control disorders (e.g. pathological gambling, compulsive shopping, hypersexuality and binge eating) and also with behavioral changes from low mood, irritability and verbal aggressiveness up to psychotic and manic symptoms and paranoid delusions not only in patients with prolactinomas but also in patients with Parkinson's disease and restless leg syndrome. They usually have de novo onset after initiation of the dopaminergic treatment and have been mainly reported in patients with Parkinson's disease, who are being treated with higher doses of dopamine agonists. Moreover, dopamine and prolactin seem to play an essential role in the metabolic pathway. Patients with hyperprolactinemia tend to have increased body weight and an altered metabolic profile with hyperinsulinemia and increased prevalence of diabetes mellitus in comparison to healthy individuals and patients with non-functioning pituitary adenomas. Treatment with dopamine agonists in these patients in short-term studies seems to lead to weight loss and amelioration of the metabolic changes. Together these observations provide evidence that dopamine and prolactin have a crucial role both in the regard and metabolic system, findings that merit further investigation in long-term studies.

Cabergoline-induced Mania in a Patient of Pituitary Microadenoma

Cabergoline, a dopamine agonist agent, is commonly used in the treatment of hyperprolactinemia, Parkinson's disease, restless leg syndrome, and antipsychotic-induced prolactin elevation. It is generally well tolerated as compared to other dopamine agonist agents due to its more selective D2 receptor agonistic effect. We present a case of a 25-year-old female who developed manic episode, following the use of cabergoline for treatment of pituitary microadenoma. We suggest that physicians should carefully screen patients before initiating cabergoline therapy and at-risk patients may benefit from more frequent monitoring and cessation of therapy at the earliest safe juncture.

Successful treatment of a prolactinoma with the antipsychotic drug aripiprazole

In this report, we describe a female patient with both prolactinoma and psychotic disorder who was successfully treated with aripiprazole, a partial dopamine 2 receptor agonist. During the follow-up of more than 10 years, her psychotic symptoms improved considerably, prolactin levels normalised and the size of the prolactinoma decreased. This observation may be of clinical relevance in similar patients who often are difficult to treat with the regular dopaminergic drugs.