All antipsychotics lead to significant weight gain, a drug safety review has found.
Weight gain linked to the drugs, often prescribed off-label for people with autism, can increase the risk of diabetes and heart disease.
Barbara Barton, a psychologist, led the research at Ludwig Maximilian University of Munich.
The researchers have warned that medics should offer people at high risk “lifestyle interventions” or other medication.
Advice to routinely monitor weight
Barton released a statement. She said medics should routinely weigh patients who were starting treatment with any medication linked to weight gain, including antidepressants. This should happen “during the first weeks and months”, she said.
She added: “If a weight gain of 4-5 per cent occurs, a treatment change (changing to a different medication with a better metabolic profile) should be considered.
“Diet advice and increasing physical activity should also be recommended.”
But she added that studies have shown lifestyle interventions to achieve only “rather small” effects for people on antipsychotics.
And new research needs to identify tools for predicting patients at risk of gaining weight on antipsychotics, she said.
Son became obese on antipsychotic
Isabelle Garnett works as a lived experience advisor for STOMP and STAMP, the NHS England campaigns to reduce inappropriate psychotropic medication use among those with autism and learning disabilities.
She said her son Matthew, 19, who has autism and a learning disability, became obese when a doctor put him on an antipsychotic at nine years old.
Garnett said Matthew later lost weight while doctors gave him the drug at a mental health hospital, but this was because he was having only one meal a day.
The campaigning mother, from London, said antipsychotic use is a “huge concern for many families” of those with autism and learning disabilities.
Barton’s weight gain review appears in the journal Expert Opinion on Drug Safety.
Published: 31 January 2020