The Metabolic Effects of Antipsychotics

Antipsychotics are drugs with the potential to induce really important changes in the metabolism of different substances in our bodies. However, what are their effects? Read on to find out.
The Metabolic Effects of Antipsychotics
Gorka Jiménez Pajares

Written and verified by the psychologist Gorka Jiménez Pajares.

Last update: 07 June, 2023

Antipsychotic drugs can have really undesirable effects on our health. In fact, they can even seriously endanger our lives. However, they form the core of the treatment of psychoses. That’s because they help control the symptoms of acute psychotic episodes and prevent new ones from occurring.

Before prescribing these drugs, as a rule, professionals consider their side effects (Burchinski, 2023). These effects occur because the therapeutic effect of each antipsychotic is broadly similar. Since pharmacotherapy with antipsychotics is usually prolonged and often lasts for years, a recent study analyzed their metabolic effects.

Tablets
According to Angélica Burchinski, it’s likely that the metabolic side effects of antipsychotics contribute to the 14.5-year reduction in the lifespan of schizophrenia sufferers.

The metabolic effects of antipsychotics

One of the main metabolic effects of antipsychotic drugs is an increase in weight. The increase could be due to drug-induced changes in the way the body metabolizes cholesterol and triglycerides. This metabolic effect is called dyslipidemia. In addition, alterations in the normal balance of sugar or glucose in the blood also occur as a consequence of the alterations in insulin.

Weight gain has been associated with elements of risk of morbidity and death, such as cardiovascular diseases. More particularly, heart attacks and strokes. Furthermore, individuals who put on weight as a result of pharmacotherapy experience a lower quality of life (Burchinski, 2023).

“There is evidence to support increased insulin resistance, hyperglycemia, and diabetes mellitus in patients taking antipsychotics, which could reduce their life expectancy.”

-Benjamín Cortés-

Often, these effects translate into the fact that the patient abandons the drug. As a result, the treatment stops working and their psychotic symptoms reappear.

Weight gain

Drugs such as risperidone or brexpiprazole can cause increases of up to two kilograms per patient. Drugs that have been associated with a greater increase in weight often induce more intense changes in the usual lipid and glucose profiles. Among the drugs that most produce these secondary metabolic effects are chlorpromazine, olanzapine, and ziprasidone (Burchinski, 2023).

This is typically labeled metabolic syndrome. The syndrome, in addition to causing the above effects, includes a predisposition to the development of thrombi and inflammation. The latter is due to the effect of the antipsychotic on a protein known as C-reactive protein (Cortés, 2011). This syndrome has been found in almost 40 out of 100 patients undergoing antipsychotic treatment.

“The appearance of metabolic syndrome is becoming one of the main public health problems of the 21st century, as it has been shown to increase the prevalence of cardiovascular disease up to three times.”

-Benjamín Cortés-

Woman taking pill
Metabolic syndrome predisposes to the development of thrombi and inflammation.

What do the metabolic effects of antipsychotic drugs mean?

Current evidence indicates that, for every kilogram gained as a result of taking antipsychotics, the probability of developing cardiovascular disease increases by about three percent. Moreover, the more pronounced the weight gain as a result of the antipsychotic, the more altered the lipid and glucose profiles will be.

However, the weight gain tends to reach a peak and level off. For example, in the aforementioned study, they claim that men who took five or more milligrams of olanzapine daily gained almost five kilograms after six weeks of treatment. This later stabilized and they subsequently gained a little less than one and a half kilograms.

Therefore, it appears that the metabolic effects of antipsychotics tend to normalize in the long term. It seems that chlorpromazine could be the antipsychotic that produces the most spectacular weight gain. As we outlined earlier, it appears that the drugs that most destabilize the weight of patients are those that most interfere with glucose and lipid profiles. This points to chlorpromazine as a drug with potential metabolic side effects.

The need for further research

More research on this subject is required. It’s also well known that there are other individual variables that affect susceptibility to weight gain. For example, diet, the degree of physical exercise or a sedentary lifestyle, and the level of quality of care medicine received by patients.

Psychiatry professionals are aware of all of the above and of the new advances in research that occur on a daily basis. Consequently, they know how to recognize any alarm signals and can act accordingly. Fortunately, this minimizes the impact of any undesirable metabolic effects.

“Since schizophrenia is often a chronic disorder, these findings should be given more consideration than short-term data in the choice of drugs.”

-Angelica Burchinski-


All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.


  • Burschinski, A., Schneider-Thoma, J., Chiocchia, V., Schestag, K., Wang, D., Siafis, S., Bighelli, I., Wu, H., Hansen, W.-P., Priller, J., Davis, J.M., Salanti, G. and Leucht, S. (2023), Metabolic side effects in persons with schizophrenia during mid- to long-term treatment with antipsychotics: a network meta-analysis of randomized controlled trials. World Psychiatry, 22: 116-128. https://doi.org/10.1002/wps.21036
  • Cortés Morales, B. (2011). Síndrome metabólico y antipsicóticos de segunda generación. Revista de la Asociación Española de Neuropsiquiatría, 31(2), 303-320.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.