March 30, 2026

expert reaction to study looking at fluvoxamine (an antidepressant), metformin, and long COVID fatigue

A study published in the Annals of Internal Medicine looks at the antidepressant fluvoxamine and metformin for fatigue in patients with Long Covid. 

Prof Christiaan Vinkers, Psychiatrist and Stress & Resilience chair, Amsterdam University Medical Centre, said:

“This randomized placebo-controlled trial provides encouraging evidence that fluvoxamine may reduce fatigue in a selected group of patients with long COVID.  The study appears methodologically solid, with low dropout and a consistent signal on fatigue and quality of life.  Still, the findings should be interpreted cautiously because the main outcome was self-reported and the population excluded important groups such as patients with depressive or anxiety disorders.  In addition, the study focused primarily on fatigue and did not assess other long COVID features such as post exertional malaise (PEM), autonomic symptoms including POTS, or cognitive impairment, nor did it include biomarker measures to help understand underlying mechanisms.  The results are promising, but replication is essential, ideally in broader patient groups and with outcomes that capture the full spectrum of long COVID.”

‘The Effect of Fluvoxamine and Metformin for Fatigue in Patients With Long COVID: An Adaptive Randomized Trial’ by Gilmar Reis et al. was published in Annals of Internal Medicine at 22:00 UK time on Monday 30 March 2026. 

DOI: 10.7326/ANNALS-25-03959

Declared interests

Prof Christiaan Vinkers: “I am involved in an RCT on fluvoxamine in long COVID (https://projecten.zonmw.nl/nl/project/selectieve-serotonine-heropname-remmers-bij-post-covid-esprit), which is also a COI for me.”