Which drug has an oral dose equivalent to chlorpromazine?

Which drug has an oral dose equivalent to chlorpromazine?

• A. Olanzapine
• B. Loxapine
• C. Clozapine
• D. Risperidone

Answer: (B)

Understanding how the potency of antipsychotics is compared through equivalent oral doses is key here. Loxapine is a phenothiazine like chlorpromazine and has a very similar clinical potency and receptor binding profile, especially at the D2 receptor. Because of that similarity in effect, the amount of loxapine needed to achieve a comparable antipsychotic effect to a given dose of chlorpromazine tends to be in the same general range. That makes loxapine the best match among the options for an oral dose equivalent to chlorpromazine. The other drugs listed are atypical antipsychotics with different potencies and dosing conventions, so their equivalent chlorpromazine doses aren’t as straightforward or standardized in the same way.

Understanding how the potency of antipsychotics is compared through equivalent oral doses is key here. Loxapine is a phenothiazine like chlorpromazine and has a very similar clinical potency and receptor binding profile, especially at the D2 receptor. Because of that similarity in effect, the amount of loxapine needed to achieve a comparable antipsychotic effect to a given dose of chlorpromazine tends to be in the same general range. That makes loxapine the best match among the options for an oral dose equivalent to chlorpromazine. The other drugs listed are atypical antipsychotics with different potencies and dosing conventions, so their equivalent chlorpromazine doses aren’t as straightforward or standardized in the same way.