Common antidepressant can treat long COVID fatigue symptoms: study

Empty COVID-19 vaccine vials are shown at a pharmacy in Toronto on Wednesday, April 6, 2022. (THE CANADIAN PRESS/Nathan Denette)

A common and low-cost antidepressant can successfully treat fatigue associated with long COVID, according to a new study.

Co-led by researchers from McMaster University in Ontario, the study found that the drug fluvoxamine, which is commonly sold under the name Luvox, significantly reduced fatigue symptoms in a clinical trial of 399 adults with long COVID. It is one of the first times a medication has been shown to effectively treat the condition.

“This is an important step forward for patients who have been desperate for evidence‑based options,” senior author and McMaster University professor Edward Mills said in a news release.

“Fluvoxamine showed consistent and meaningful benefits, and because it’s already widely used and well understood, it has clear potential for clinical use.”

An estimated 65 million people worldwide have experienced long COVID. Also known as post COVID-19 condition, or “PCC” for short, the World Health Organization says common symptoms include fatigue, breathlessness, muscle or joint pain and impaired sleep that persist for at least three months after an initial COVID-19 infection.

“PCC can affect a person’s ability to perform daily activities, such as work or household chores and restrict social participation,” the World Health Organization says. “Global estimates indicate that six in 100 people with COVID-19 develop post COVID-19 condition.”

‘First strong evidence’

The clinical trial also tested the effectiveness of the common diabetes medication metformin. Although previous research has demonstrated that metformin can reduce the risk of developing long COVID if taken during an infection, the new study showed that it does not treat long COVID fatigue symptoms.

Mills – who teaches in McMaster’s Department of Health Research Methods, Evidence, and Impact – says the research team wanted to focus on existing, widely available and affordable medications that could help with long COVID symptoms.

“Both had biological reasons to think they might work against long COVID fatigue, but neither had been rigorously tested for this purpose in a proper clinical trial,” he explained.

Researchers from Canada, Brazil and the U.S. contributed to the study, which included partners from the University of British Columbia. Conducted in Brazil, the 60-day clinical trial showed a 99 per cent probability that fluvoxamine outperformed the placebo for reducing fatigue symptoms. Fluvoxamine also led to reported quality of life improvements. Generic versions of the drug can cost less than $1 per tablet.

“This trial gives clinicians their first strong evidence for a medication that helps reduce long COVID fatigue,” corresponding author and University of British Columbia postdoctoral research fellow Jamie Forrest said in the news release. “Patients want something they can try today – and this finding brings us closer to that reality.”

The study will be published on March 31 in the Annals of Internal Medicine, a peer-reviewed journal published by the American College of Physicians.