New Study Links Constipation Drug to Better Cognitive Function in Depression

A medicine normally used to treat chronic constipation may also help improve memory, focus, and thinking skills in people who have recovered from depression, according to a new study published in Psychological Medicine.

Many people continue to experience brain fog, poor concentration, and memory problems even after their depression gets better. Researchers wanted to see if prucalopride, a constipation medicine, could help reduce these symptoms.

The study involved 50 adults who had recovered from depression at least six months earlier and were not taking antidepressants. Participants were randomly given either 2 mg of prucalopride or a placebo (dummy pill) every day for 7 to 10 days.

Before and after the treatment, they completed tests that measured memory, attention, learning ability, and thinking speed.

The results showed that people who took prucalopride performed better on memory and attention tests than those who took the placebo. They answered questions more quickly and more accurately, suggesting an improvement in overall thinking ability.

Researchers also found that the medicine was well tolerated, with no serious side effects reported during the study. Although prucalopride is used as a laxative, participants did not experience major stomach or bowel problems.

The researchers believe the drug works by activating a serotonin receptor called 5-HT4, which is found not only in the gut but also in the brain. This may help improve the brain functions that are often affected by depression.

However, the researchers say this was a small, short-term study, so the findings need to be confirmed in larger clinical trials.

Overall, the study suggests that prucalopride may one day become a new treatment for brain fog and memory problems that continue even after depression has improved, but more research is needed before it can be used for this purpose.

REFERENCE: Angharad N. de Cates, Sorcha Hamilton, Anutra Guru, Merethe Blandhol, Michael Colwell, Philip J. Cowen, Meghan Simmons, Bailey Jones, Catherine J. Harmer, Susannah E. Murphy. Pro-cognitive effects of 5-HT4 receptor agonism in individuals with remitted depression. Psychological Medicine, 2026; 56 DOI: 10.1017/S0033291726104450