Which of the following antipsychotic drugs are available as an injectable depot preparation?
**Core Concept**
The antipsychotic depot preparations are long-acting injectable formulations used to treat schizophrenia and other psychiatric disorders. These depot preparations provide a sustained release of the medication, reducing the need for daily oral dosing and improving patient compliance.
**Why the Correct Answer is Right**
Haloperidol decanoate is a long-acting injectable form of haloperidol, a typical antipsychotic. It is formulated as a sterile suspension, which is injected into the gluteal muscle every 4 weeks. Haloperidol decanoate provides a slow release of haloperidol, maintaining therapeutic plasma concentrations for an extended period. This formulation is particularly useful for patients with schizophrenia who have difficulty adhering to oral medication regimens.
**Why Each Wrong Option is Incorrect**
* **Option A:** Risperidone is available as a long-acting injectable formulation, but it is not typically referred to as a depot preparation. Risperidone long-acting injection (RLAI) is a microspheres formulation that provides a sustained release of risperidone.
* **Option B:** Olanzapine is not available as a long-acting injectable depot preparation. However, olanzapine pamoate, a long-acting injectable formulation, is available for the treatment of schizophrenia.
* **Option D:** Quetiapine is not available as a long-acting injectable depot preparation.
**Clinical Pearl / High-Yield Fact**
When using antipsychotic depot preparations, it is essential to monitor patients for potential side effects, such as extrapyramidal symptoms, tardive dyskinesia, and metabolic disturbances. Regular follow-up appointments are crucial to adjust the dosage and manage any adverse effects.
**Correct Answer:** B.