Antipsychotics: Nursing pharmacology

Antipsychotics are medications mainly used to treat schizophrenia and other psychotic disorders, such as psychosis, acute mania, delirium, bipolar disorders, and obsessive-compulsive disorders. Antipsychotics are most often administered orally, but some can also be sublingual or transdermal, or injected intramuscularly, intravenously, or subcutaneously.

Once administered, they travel to the brain and block dopamine D2 receptors in the mesolimbic pathway, thereby helping alleviate some psychotic symptoms. Now, there are two main groups of antipsychotics: the first-generation or typical antipsychotics, and the second-generation or atypical antipsychotics.

Typical antipsychotics can be further classified as high-potency or low-potency medications. High-potency antipsychotics include medications such as haloperidol, trifluoperazine, and fluphenazine. These medications have a high affinity for dopamine receptors, meaning they require lower doses to achieve their therapeutic effect. On the flip side, low-potency antipsychotics include medications such as thioridazine and chlorpromazine.

These medications have less affinity for dopamine receptors, therefore they require larger doses to achieve the same therapeutic effect as high-potency antipsychotics.

On the other hand, second generation, or atypical antipsychotics, include medications such as clozapine, olanzapine, quetiapine, risperidone, and ziprasidone. In addition to blocking dopamine D2 receptors, atypical antipsychotics also work by blocking serotonin 5-HT2A receptors in the mesocortical pathway. Another atypical antipsychotic is asenapine, which is administered sublingually or transdermally, to prevent clients from “cheeking” their medication; that’s when a client pretends to swallow their medication, but instead keeps it hidden between the teeth and the cheek.