Are there specific medications to reduce symptoms in Severe Mental Illness?
Severe mental illness (SMI) includes conditions like schizophrenia, bipolar disorder, and major depression. The main medications used to reduce symptoms are antipsychotic drugs, which help with delusions and hallucinations 9. However, these drugs often cause weight gain. Metformin is the only medication proven to prevent that weight gain 7. Other drugs, like antithrombotic agents (e.g., aspirin), have been studied but the evidence is very weak 6.
What the research says
Antipsychotic medications are the cornerstone of treatment for schizophrenia and related disorders. They effectively reduce positive symptoms such as delusions and hallucinations 9. However, up to half of people prescribed these drugs do not take them as directed, which can lead to relapse 9.
Weight gain is a common and distressing side effect of antipsychotics. A 2025 guideline found that metformin, when started at the same time as an antipsychotic, can reduce weight gain by about 4 kg (almost 9 pounds) compared to placebo 7. This is the only medication shown to prevent antipsychotic-induced weight gain 7.
A 2024 systematic review looked at antithrombotic agents (blood thinners like aspirin) for SMI. It found that these drugs may reduce depressive symptoms, but the evidence is very low certainty 6. The same review found that antithrombotic agents may also reduce total symptom scores in schizophrenia, again with very low certainty 6. Tolerability was similar to placebo 6.
Other research has explored how mental illness affects treatment outcomes. For example, people with mental illness who undergo weight loss surgery tend to lose less weight than those without mental illness 1. And after a hospital stay for psychiatric care, certain factors can predict who will need emergency care again 5.
What to ask your doctor
- What antipsychotic medication is best for my specific symptoms and side effect profile?
- If I am starting an antipsychotic, should I also take metformin to prevent weight gain?
- Are there any other medications that might help with my symptoms if antipsychotics are not enough?
- How can I improve my adherence to medication to reduce the risk of relapse?
- What should I watch for in terms of side effects, and when should I contact you?
This question is drawn from common patient questions about Psychiatry and answered using cited medical research. We do not provide individualized advice.