Going on—and staying on—antipsychotic medications is key to keeping psychotic and mood disorder symptoms at bay. Unwelcome side effects, including weight gain, have long been a barrier for some patients to doing so.
According to psychopharmacology specialist Dr. Joseph E. Comaty, antipsychotic drugs are divided into three categories based on when they came onto market: first generation drugs including chlorpromazine and haloperidol, second generation drugs like clozapine and olanzapine, and third generation drugs like aripiprazole. The risk of gaining weight ranges within each class.
Antipsychotics block dopamine receptors and affect serotonin receptors. However, the exact reason they have a propensity to add pounds remains somewhat of a mystery.
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Theories suggest that these drugs may increase appetite cues in users. People on these drugs may feel hungrier as a result and therefore tend to eat more. “Some people think it’s related to one of the serotonin receptor types, 5HT6 in particular. Comaty told Psychiatrist.com that confirmation for this idea is lacking.
Antipsychotic Medication Differences
While the newer generation of medications may cause lesser weight gain “in the order of 7-10 pounds,” Comaty said, drugs like clozapine and olanzapine have been known to cause a more than seven percent increase in users’ body weight.
“I’ve known patients to gain on the order of 20-30 pounds. Some of that depends on what their initial baseline body weight is,” he said. Third generation antipsychotics, which are newer to the market, have been associated with lesser weight gain but they aren’t always the best option for every patient, he added.
When considering treatment options for patients, physicians take various factors into consideration to find the best match for the individual’s overall health.
“There’s cost, there’s the frequency of dosing, there are metabolic concerns,” Comaty said.
For example, antipsychotics that are known to produce the most weight gain—clozapine and olanzapine—are less expensive than third generation antipsychotics like aripiprazole, paliperidone, and ziprasidone, meaning they might be a better choice for individuals without insurance coverage. Other patients have diabetes, “so you’d want to be cautious about prescribing an antipsychotic that may have a higher risk of exacerbating their diabetes,” he added.
In addition, not all patients respond well to third generation antipsychotics. “Indeed, a drug that produces weight gain may be the best or most effective drug for their schizophrenic or bipolar or depressive symptoms,” Comaty said.
Patient Reticence
A thickening waistline can be a barrier for some patients to take their meds regularly. “There’s some recent articles that looked at patient attitudes towards medications and the reasons why they might discontinue treatment, and one of the issues that arose in those surveys was that the drugs produced weight gain,” Comaty noted.
A prominent issue remains that patients, many of whom see their psychiatrists just two or three times a year, often develop concerns about their medication between appointments. They sometimes stop taking antipsychotic medications without consulting their provider. The result? “The side effects may go away, but then, of course, their psychiatric symptoms may return and that creates a whole ‘nother series of risks for the individual,” said Comaty.
Comaty urged patients to consult with their psychiatrists before stopping treatment, acknowledging that patient concerns may be valid. Together they may be able to find a suitable solution. Often, patients must undergo a trial and error approach with their medications to assess the pros and cons, including a rising number on the bathroom scale. “Even so,” Comaty said, “the person may have to understand how to live with some of the downsides to these medications in order to maximize the probability that they remain a functional individual.”
Advising Patients
When advising patients who have weight concerns, Comaty recommended that clinicians take a thoughtful and transparent approach. Providing the patient as much information as possible and including them in the treatment plan makes them more likely to stay the course.
“Tell them what the risks and benefits of the medication are and what you would do to work with them on mitigating those side effects,” Comaty suggested. For patients concerned about their weight in particular, Comaty said don’t sugarcoat the truth: Weight gain is possible. Also, explain that it’s manageable with certain interventions.
Clinicians can suggest solutions like diet plans, exercise programs, or simply opting for the medication with the least risk for producing weight gain. Consider some new options, too. Diabetes drugs like Ozempic and Wegovy, which are known to slow digestion and facilitate weight loss, are becoming an increasingly popular choice for antipsychotic users to counteract weight gain.
