Children, Medicines & Metabolic Health
Second-generation, or “atypical,” antipsychotic medicines can be very important for some children and adolescents with serious psychiatric or behavioral conditions. They can also cause weight gain and changes in glucose and lipids. The goal is not to frighten families away from needed treatment, but to monitor metabolic health from the beginning and respond early if problems appear.
Rapid weight gain can appear during the first weeks to months of treatment, especially in children who have not taken antipsychotics before.
Olanzapine and clozapine generally have greater metabolic liability; other agents may have lower—but not zero—risk.
Weight, growth, blood pressure, glucose or HbA1c, lipids and other adverse effects should be followed systematically.
Atypical antipsychotics are more accurately called second-generation antipsychotics (SGAs). They affect dopamine and other neurotransmitter systems and are used for selected psychiatric and neurodevelopmental conditions.
Depending on the specific medicine, age, diagnosis and country, pediatric indications can include schizophrenia, bipolar disorder, irritability associated with autism spectrum disorder, and Tourette syndrome. Antipsychotics are also sometimes prescribed off label for other severe symptoms when a specialist believes the potential benefit justifies the risk.
They can increase the risk, but “cause” is too absolute for every child. Second-generation antipsychotics are associated with metabolic dysregulation that can include increased appetite, weight gain, higher BMI, abnormal lipids, insulin resistance and elevated glucose.
ADA 2026 notes that adolescents and adults prescribed second-generation antipsychotics should have body weight, glycemia and lipids monitored because these medicines can worsen metabolic risk.
Some glucose effects may occur partly through weight gain and increased adiposity, while other drug effects on insulin sensitivity and metabolism may also contribute.
The exact ranking varies across studies and populations, but pediatric evidence has been consistent that metabolic effects are not identical across medicines.
| General metabolic tendency | Examples | Clinical meaning |
|---|---|---|
| Higher | Olanzapine, clozapine | Greater concern for weight gain and metabolic abnormalities; careful monitoring is particularly important. |
| Intermediate | Risperidone, quetiapine, paliperidone | Weight and metabolic changes can still be clinically important and vary by child. |
| Generally lower | Aripiprazole, lurasidone, ziprasidone | Lower average metabolic liability does not mean “metabolically neutral” or risk-free. |
In pediatric trials and cohort studies, olanzapine has repeatedly produced some of the largest average weight gains. Even medicines with lower average risk can cause substantial weight gain in an individual child.
Children are still growing, and antipsychotic-related changes must be interpreted in the context of age, sex, height and normal development. Weight should therefore be plotted on a pediatric growth chart rather than judged only by an adult BMI number.
Young people who are receiving an antipsychotic for the first time may gain weight rapidly. A recent 2025 systematic review again found significant associations between second-generation antipsychotic treatment, weight gain, increased BMI and metabolic changes in children and adolescents.
One evidence-based pediatric approach is to document baseline physical and metabolic health before the first dose whenever possible.
Monitoring schedules differ somewhat among professional organizations, but they agree that metabolic monitoring should begin early and continue throughout treatment.
| Time | What to consider |
|---|---|
| Before starting | Weight/height/BMI, blood pressure, fasting glucose or HbA1c, lipids, diet/activity and relevant adverse-effect baseline measures. |
| First 6 weeks | NICE pediatric guidance recommends frequent weight monitoring because early weight change can be rapid. |
| About 12–16 weeks | Repeat diabetes screening; pediatric guidance also reassesses weight, blood pressure, glucose/HbA1c and lipids around this period. |
| Ongoing | Pediatric NICE guidance uses 6-month metabolic follow-up; ADA recommends at least annual diabetes screening after the early repeat, with earlier testing when clinically indicated. |
A child who gains weight rapidly, develops symptoms of high glucose or has strong pre-existing diabetes risk may need testing sooner.
When laboratory testing is performed, the standard ADA diagnostic thresholds are used, but results in children must still be interpreted by the treating clinician.
| Test | Prediabetes | Diabetes |
|---|---|---|
| HbA1c | 5.7–6.4% | ≥6.5% |
| Fasting plasma glucose | 100–125 mg/dL (5.6–6.9 mmol/L) | ≥126 mg/dL (7.0 mmol/L) |
| 2-hour OGTT glucose | 140–199 mg/dL (7.8–11.0 mmol/L) | ≥200 mg/dL (11.1 mmol/L) |
In the absence of unequivocal hyperglycemia, an abnormal result generally requires confirmation with repeat testing or another diagnostic test.
Laboratory monitoring is important because early hyperglycemia may cause no symptoms. When symptoms do occur, they may include:
Vomiting, abdominal pain, dehydration, deep or rapid breathing, unusual sleepiness, confusion or a fruity-smelling breath can be warning signs of a serious metabolic emergency and should not wait for a routine appointment.
Weight gain is one of the most common metabolic concerns with second-generation antipsychotics. It can begin early and may be substantial in some children.
That does not mean the medicine should automatically be stopped. Instead, rapid or excessive weight gain should trigger review of:
Healthy lifestyle support should begin when treatment begins, not after a large amount of weight has already been gained.
Families can focus on water instead of sugar-sweetened beverages, regular meals, nonstarchy vegetables, whole fruits, legumes, whole grains in appropriate portions, lean protein and fewer highly processed snacks.
Regular age-appropriate physical activity and adequate sleep also matter. But parents should not be blamed if metabolic changes occur despite good habits—the medicine itself, the underlying condition, genetics and individual biology may all contribute.
Not abruptly and not without the prescriber.
If metabolic abnormalities appear, the psychiatric and medical teams should review the benefit-risk balance. Depending on the situation, options may include intensifying lifestyle support, adjusting the dose, changing to another medication with lower metabolic risk when clinically appropriate, or treating the metabolic problem directly.
Metabolic effects are only one part of antipsychotic safety. Depending on the medicine, children may also develop:
Akathisia, tremor, stiffness, dystonia and tardive dyskinesia can occur.
Drowsiness may affect school performance, activity and daily functioning.
Some medicines can raise prolactin and cause menstrual changes, breast symptoms or other endocrine effects.
Blood pressure, heart rate and—when clinically indicated—electrocardiographic effects may need attention.
Insulin resistance means the body's tissues do not respond to insulin as effectively as they should. The pancreas compensates by producing more insulin, but over time glucose may begin to rise.
Antipsychotic-associated weight gain can worsen insulin resistance, but some metabolic effects may occur independently of weight change. This is one reason glucose monitoring is still needed even if a child's weight has not changed dramatically.
Learn more in our guide to insulin resistance .
I would not want a parent to refuse a necessary psychiatric treatment simply because they read that antipsychotics can cause diabetes. Untreated serious mental illness can also have major consequences for a child's health, education, relationships and safety.
What I do want is a clear metabolic plan from day one. Before treatment, document the child's growth, blood pressure, glucose or HbA1c and lipids. Then watch weight closely in the early weeks and repeat the metabolic tests on schedule.
If a problem starts to develop, that is the time for the psychiatrist, pediatrician, family and—when needed—endocrinologist to work together. Early recognition gives us more options than waiting until a child has established type 2 diabetes.
No. Risk increases with some medicines, but most treated children do not automatically develop type 2 diabetes.
Pediatric evidence consistently places olanzapine among the highest-risk agents for weight gain. Clozapine also has high metabolic liability but is used for specific clinical situations.
No. Its average metabolic risk is lower than olanzapine in many studies, but individual children can still gain clinically important weight.
Current guidance supports baseline glucose screening with fasting glucose or HbA1c, followed by early repeat testing and ongoing monitoring.
Understand what insulin resistance means and how it relates to type 2 diabetes.
Read about insulin resistance →Learn how fasting glucose, HbA1c and other tests are interpreted.
Explore diabetes testing →Understand the causes, diagnosis and treatment of type 2 diabetes.
Learn about type 2 diabetes →Learn why lipid monitoring matters when metabolic risk increases.
Explore cholesterol and diabetes →