June 19, 2026, 11:37 am | Read time: 3 minutes
Not only frees the gut but apparently also the soul: A medication originally used for constipation alleviates cognitive depression symptoms after just one week. These are symptoms that often persist after recovery. FITBOOK explains the background.
It often happens that certain side effects of some medications turn out to be a blessing. This is also the case with prucalopride, a drug used to treat chronic constipation. It helps with ailments that become particularly noticeable when the depression itself has been overcome. These include lack of concentration, poor memory, or a foggy feeling when thinking (brain fog). These so-called cognitive residual symptoms can make returning to everyday life difficult. Prucalopride, an already approved and cost-effective medication, offers hope of finally getting rid of these burdensome depression symptoms. The study results were recently published in the journal “Psychological Medicine.”1
How a Constipation Medication Can Help with Depression Symptoms
Prucalopride activates the 5-HT4 receptor, which is a docking site for the neurotransmitter serotonin. This neurotransmitter is responsible not only for satisfaction but also for learning and memory, emotional processing, and communication between nerve cells. Previous studies in mice had shown that activating this receptor could support neuroplasticity. If depression impairs certain thought processes, the assumption is that targeted influence could help strengthen mental performance. Researchers from Oxford University and the University of Birmingham have now investigated this question in humans.
Substance Administered to 50 Adults with Resolved Depression
For the study, 50 patients (ages 18 to 40) who had previously experienced depressive episodes were recruited. It was crucial that the depression had already subsided. Participants were randomly given either two milligrams of prucalopride, a dose currently approved only for chronic constipation, or a placebo for seven to ten days. Before and after taking the medication, each participant completed a series of cognitive tests, including:
- Memory
- Working memory
- Attention
- Processing speed
- Emotional perception
Also of interest: Popular seasoning may help with depression
Surprising Results
The prucalopride group was able to reliably remember previously heard words compared to the placebo group after taking the medication. This suggests that the drug could improve the ability to absorb and recall new information. The prucalopride group also responded significantly faster in a task that required retaining information in memory while tracking new information. Particularly surprising: Prucalopride apparently helped to more accurately recognize emotions (such as fear, joy, anger, or surprise) in faces that were visible for only half a second. Overall, those who received prucalopride performed significantly better on several cognitive tests than the placebo group.
The medication was well tolerated but led to reduced appetite in some participants.
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Study Offers Hope, but No Help Yet
For those who have overcome depression but still feel mentally slowed down, there are currently no approved therapies. “Many people overcome depression, but concentration and memory often take longer to recover. Our results show initial indications that activating the 5-HT4 receptor could help specifically support these cognitive functions,” said study leader Prof. Susannah Murphy in a university statement.2 Unfortunately, the study is too small and the study period too short. It is not conclusive enough to use the medication for the mentioned depression symptoms at this time.
Many Questions Remain Unanswered
Despite the promising initial results, it is unclear how the constipation medication will affect cognitive depression symptoms in the long term. Will the effect persist? Does the approach work for currently depressed individuals or older people? Could longer use potentially have problematic side effects? All of this needs to be clarified in follow-up studies, which, according to the University of Birmingham, are already being planned.