When choosing an antipsychotic for acute treatment of psychosis, evaluating the drug's side effects is an important step, Stephen Marder, MD, of the Semel Institute for Neuroscience at the University of California Los Angeles, said at a session presented at the Nevada Psychiatric Association’s 26th Annual National Psychopharmacology Update.
“The largest consideration is usually adverse effects. The differences in efficacy are relatively minor; the differences in side effects can be substantial,” Dr. Marter told virtual attendees.
Except for clozapine, the differences in the effectiveness of the available drugs are minor, he explained. Therefore, if clinicians or patients are concerned about specific side effects such as weight gain or sexual dysfunction, those considerations can help lead to a particular antipsychotic over another option, Dr. Marter said.
When evaluating if the selected antipsychotic is effective, Dr. Marter suggested following a general timeline of assessment. “Side effects early on are evidence a patient isn't being properly treated with a drug,” he said.
He told attendees to evaluate patients’ response to the antipsychotic in 2 to 3 weeks. If there is a partial response, continue treatment for 6 to 12 weeks. If there is no response or severe side effects, switch medications.
Some patient symptoms might appear to be side effects, Dr. Marter noted. “Patients with delusions may talk more clearly about their thoughts and delusions which will make them seem worse, but they are just able to more clearly organize those thoughts, ” he explained.
“When selecting a long-acting injectable (LAI), keep in mind that you get a higher maximum plasma concentration from an oral drug than an LAI. That's important because the side effects are often determined more by the maximum plasma concentration than they are by the lower steady state concentration, which for some, means that the drug actually has milder side effects.”
For information on how to initiate specific antipsychotics and their dosage, Dr. Marter suggested utilizing the detailed chart on Up To Date.
“How to Choose an Antipsychotic.” Presented at: 26th Annual National Psychopharmacology Update: February 11, 2021; Virtual.