Which Atypical Antipsychotics Carry the Highest Risk for Diabetes?

Information on the diabetes risk in antipsychotic medications.

If you are unfamiliar with antipsychotics, my article, Psychosis 101, has a detailed description of the medications and how they work. The following information on diabetes risk in antipsychotic medications comes from two papers from the Journal of Clinical Psychiatry: Antipsychotic Medications: Metabolic and Cardiovascular Risk by Dr. John W. Newcomer and Switching Antipsychotics as a Treatment Strategy for Antipsychotic-Induced Weight Gain by Dr. Peter J. Weiden. Both researchers show conclusive evidence that the risk of diabetes from certain antipsychotics is high and must be addressed immediately within the entire healthcare community.

There are six atypical antipsychotics in use today:

(a newer antipsychotic called Saphris was not a part of the metabolic syndrome studies cited in the article.)

Numerous and well-documented studies have shown a serious and potentially dangerous connection between certain second-generation antipsychotics and the risk of diabetes because of their connection to metabolic syndrome. Those atypical antipsychotics with the highest risk for developing diabetes are:

  • Clorazil (clozapine)
  • Zyprexa (olanzipine)

In a major NIMH study (the CATIE project), Zyprexa was associated with relatively severe metabolic effects. Subjects taking Zyprexa showed a major weight gain problem and increases in glucose, cholesterol, and triglycerides. The average weight gain over the 18-month study period was 44 pounds.

Medium risk antipsychotics are:

  • Seroquel (quetiapine)
  • Risperdal (risperidone)

Abilify and Geodon do not have a significant risk of metabolic syndrome and thus are not considered a diabetes risk (although the FDA has ordered all makers of antipsychotic drugs to include a warning about a possible link with diabetes on their product label). The term high-risk antipsychotics used throughout this article refers to Clozaril and Zyprexa and, in some cases, Seroquel and Risperdal.

Average Weight Gain From Atypical Antipsychotics

The percentages in the list below represent the typical long-term weight gain associated with each atypical antipsychotic drug. For example, a person who weighs 100 pounds before taking Zyprexa, on-average gains 28 pounds after starting the medication. Of course, all of these numbers are averages, but they are supported by numerous research studies.

Zyprexa (olanzipine) > (more than) 28% weight gain (High diabetes risk due to an increase in glucose levels. Zyprexa has the highest average weight gain of 2 lbs a month.)

Clozaril (clozapine) >28% weight gain ( High diabetes risk due to an increase in glucose levels.)

Seroquel (quetapine) > 23% (Not enough research to associate the weight gain from Seroquel to a high diabetes risk - though risk seems to be moderate as there can be significant weight gain.)

Risperdal (risperidone) > 18% (Risperdal can cause weight gain but is considered at a lower risk for causing diabetes.)

Geodon (ziprazidone) < 10% (Considered weight neutral. There is no known diabetes risk in Geodon and some studies have found that it improves metabolic variables.)

Abilify (aripiprazol) <8% (Considered weight neutral. There is no known diabetes risk with Abilify and in some cases has lead to mild weight loss.)

(ED. NOTE: The FDA ordered all pharmaceutical manufacturers to include in their product label that antipsychotics carry a risk of diabetes.)

The time it takes to gain the weight varies. For some, it's within a few months, for others it happens over years. Some of the weight gain stops at a certain point, while other drugs cause weight gain that continues until a person stops the drug. As mentioned before, this weight gain often happens without a change in diet or exercise for the patient, though it's also very common for the drugs to increase the appetite to an obsessive point and the person never feels satisfied after eating. In some cases, a person doesn't gain weight at all, in others, a person will keep gaining until they become morbidly obese.

APA Reference
Fast, J. (2022, January 4). Which Atypical Antipsychotics Carry the Highest Risk for Diabetes?, HealthyPlace. Retrieved on 2024, July 13 from

Last Updated: January 12, 2022

Medically reviewed by Harry Croft, MD

More Info