From the FDA Drug Label
2.1 Schizophrenia Adults The recommended starting and target dose for aripiprazole tablets is 10 or 15 mg/day administered on a once-a-day schedule without regard to meals Switching from Other Antipsychotics There are no systematically collected data to specifically address switching patients with schizophrenia from other antipsychotics to aripiprazole tablets or concerning concomitant administration with other antipsychotics
The appropriate initial dose of aripiprazole (Abilify) for a patient with hyperprolactinemia, currently taking haloperidol (Haldol) 50mg intramuscularly (IM) every 2 weeks and quetiapine (Seroquel) 300mg once daily, is 10 or 15 mg/day. Regarding discontinuation of quetiapine in favor of aripiprazole, the label states that there are no systematically collected data to specifically address switching patients with schizophrenia from other antipsychotics to aripiprazole tablets, and it is recommended that the period of overlapping antipsychotic administration should be minimized 1.
From the Research
I recommend starting aripiprazole at a dose of 10mg daily, as this dose has been shown to be effective in reducing prolactin levels while providing additional antipsychotic coverage, as seen in the study by 2. The patient is currently taking haloperidol 50mg IM every 2 weeks and quetiapine 300mg daily, and it is likely that the haloperidol is contributing to the elevated prolactin level. Aripiprazole, with its partial dopamine agonist properties, can help reduce prolactin levels while providing additional antipsychotic coverage. Rather than immediately discontinuing quetiapine, it's preferable to add aripiprazole first, monitor prolactin levels over 4-6 weeks, and then consider gradually tapering quetiapine if prolactin normalizes and symptoms remain controlled, as suggested by 3. This approach minimizes the risk of symptom exacerbation during medication changes. The patient should be monitored for potential side effects of this combination, including extrapyramidal symptoms, metabolic changes, and QTc prolongation. Some key points to consider when managing antipsychotic-induced hyperprolactinemia include:
- Monitoring prolactin levels regularly, as recommended by 4
- Using the lowest effective dose of the antipsychotic agent, as suggested by 5
- Considering a switch to a prolactin-sparing antipsychotic, such as aripiprazole, as seen in the study by 2
- Adding a dopamine agonist, such as cabergoline, if necessary, as mentioned in 3 If the prolactin level doesn't improve significantly after 4-6 weeks, consider gradually reducing the haloperidol dose while increasing aripiprazole to maintain symptom control. It's also important to note that aripiprazole has been shown to be effective in reducing prolactin levels in patients with antipsychotic-induced hyperprolactinemia, as seen in the study by 6. Overall, the goal is to minimize the risk of symptom exacerbation while managing the patient's hyperprolactinemia, and aripiprazole appears to be a good option for this patient.