NCT07424781

Fluoxetine on Emotional Experience (FLEX) Study

The Effect of Fluoxetine Treatment on Anger Processing in Healthy Young People

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 80 (estimated)
• Sponsor: University of Oxford · Academic / Other
• Sex: All
• Age: 18 Years – 24 Years
• Healthy volunteers: Accepted

Summary

The goal of this clinical medicine study is to investigate how does antidepressant fluoxetine modulate anger processing in healthy young people . The main questions it aims is to answer are: 1. How does fluoxetine affect responses to anger-related stimuli such as words, faces, and autobiographical recall? 2. How does fluoxetine influence responses during frustration induction in frustrative non-reward and threat paradigms? 3. Does the effect manifest in physiological markers, including heart rate variability and facial expressions? Researchers will compare fluoxetine to a placebo to see if drug fluoxetine affects anger processing. Participants will: Take 20mg fluoxetine or a placebo every day for 7 days. Visit the university site for questionnaire and tasks assessments. Heart rate variability and facial expressions will be recorded in some of the tasks.

Conditions

• Depression - Major Depressive Disorder
• Irritability
• Depression

Interventions

Type	Name	Description
DRUG	Fluoxetine	Participants will receive 20mg of fluoxetine daily for 7 days. Tablets encapsulated to aid blinding.
DRUG	Placebo	Participants will receive one dose placebo (sucrose) daily for 7 days. Tablets encapsulated to aid blinding.

Timeline

• Start date: 2025-10-01
• Primary completion: 2026-12-31
• Completion: 2026-12-31
• First posted: 2026-02-20
• Last updated: 2026-02-20

Locations

1 site across 1 country: United Kingdom