Why Some Anxiety Medications May Cause Weight Gain—and How to Manage It

Many anxiety medications, including common antidepressants, have been linked to weight gain in some patients. A review of 27 studies found that those taking antidepressants gained an average of 5% of their body weight. However, not everyone experiences this effect, and the increase can often be managed with lifestyle adjustments.

Antidepressants and other anxiety treatments—such as SSRIs, SNRIs, tricyclics, lithium, and MAOIs—are among the drugs most frequently associated with weight changes. Paroxetine, escitalopram, and duloxetine appear more likely to cause weight gain compared to other antidepressants. Some antipsychotics and mood stabilisers used for mental health conditions may also contribute to similar effects.

When untreated, anxiety can suppress appetite, but starting medication may restore it or slow metabolism. This shift can sometimes lead to gradual weight gain. However, the effect varies between individuals, and not all patients will see significant changes. Research from 2008 to 2019 highlights the trend, though no recent studies (2021–2026) have pinpointed the exact mechanisms behind weight gain in anxiety patients. Despite this, experts suggest that staying active, eating mindfully, and managing stress can help limit or prevent unwanted weight changes while on these medications.

Weight gain from anxiety medications is not inevitable, and its impact can often be modest or temporary. With proper management—such as regular exercise, balanced nutrition, and stress reduction—patients can reduce the likelihood of significant changes. The key lies in monitoring health and adjusting habits as needed.