youthree years after the COVID-19 pandemic, with millions of people around the world suffering from long-term complications of the virus, there is still no proven way to treat or prevent long-term COVID, other than not getting infected in the first place.
Recently, however, there has been cause for cautious optimism. Researchers have found promising (albeit preliminary) signs that certain drugs may reduce the risk of developing Long COVID and possibly even alleviate symptoms among people who are already sick.
The latest hopeful news concerns metformin, an accessible and affordable drug that has been approved by the US Food and Drug Administration (FDA) to treat type 2 diabetes since the 1990s. Metformin, which belongs to a class of drugs called biguanides, is Taken in liquid or pill form, it works by controlling the amount of sugar in your blood. Also decreases inflammation in the body.
In A study Published online in March but not yet peer-reviewed, researchers tracked a group of 564 overweight or obese US adults who began a two-week course of metformin when they had acute COVID-19. People who took metformin were 42% less likely to be diagnosed with COVID-19 over the next 10 months, compared to those who took a placebo when they first got sick with COVID-19. (The study also tracked the effects of the drugs ivermectin and fluvoxamine, but neither showed a benefit against Long COVID.)
Metformin seemed to be even more effective when used early. Among people who took it within four days of developing symptoms, the risk of long-term COVID was reduced by more than 60%. In all, about 6% of people who took metformin were diagnosed with long-term COVID, compared with more than 10% of people who took a placebo.
Other studies have shown Metformin can stop the replication of the SARS-CoV-2 virus, which can help prevent serious illness and long-term complications, explains study co-author Dr. Carolyn Bramante, an assistant professor at the University of California School of Medicine. University of Minnesota. Metformin appears to work against the virus by blocking a protein in human cells that the virus uses to copy itself and by disrupting the inflammatory response caused by the virus, she says.
Bramante says she was pleasantly surprised by how well metformin seemed to prevent long-term COVID, especially when taken immediately, though more research is required to confirm the findings. “It’s probably in every drug store in the world,” says Bramante. Someone is likely to “get metformin the day after they find out they have COVID.”
In the future, Bramante says, researchers should also study whether metformin can treat existing symptoms of Long COVID. Some experts believe that Long COVID is caused by remnants of the virus remaining in the body. If that’s true, Bramante says, metformin’s antiviral properties could help clear it from the body.
Other recent studies have also suggested that paxlovid, an antiviral drug used to prevent severe COVID-19 among high-risk patients, may help prevent prolonged COVID-19 in a similar way. One study, which was published online at the end of 2022 but had not been peer reviewed, found that people who took Paxlovid within five days of testing positive for COVID-19 had a 26% lower risk of developing Long COVID, compared to an untreated control group. (Ensitrelvir, another antiviral drug that is licensed in Japan but not in the US, may also reduce the risk of developing long-term COVID when taken soon after testing positive, its manufacturer announced in February.)
Some researchers are also studying whether Paxlovid can treat long-term symptoms of COVID—an important question, as there is still no proven cure for Long COVID.
Read more: People are far less likely to have long-term COVID after Omicron, study finds
Long-term COVID is difficult to treat, at least in part because the disease takes many forms. One person may have debilitating fatigue and brain fog, while another may have gastrointestinal problems or nervous system dysfunction. Instead of trying to find a single drug that can treat all long-standing cases of COVID More than 200 potential symptomssome research teams are concentrating on specific symptoms, or groups of symptoms, in the hope of finding targeted therapies.
Some tools used to treat people with myalgic encephalomyelitis/chronic fatigue syndrome, a post-viral condition which shares key symptoms with Long COVID (including extreme fatigue and post-exertion accidents), may also be effective for people with post-COVID complications, according to an article published in Nature Reviews Microbiology in January. These tools include a power rationing system strategy known as pacing, the anti-inflammatory drug naltrexone in low doses, and beta blockers to slow heart rate and lower blood pressure. antihistamines have also been shown in small studies to reduce some symptoms of prolonged COVID-19, including fatigue, brain fog, and inability to exercise, as well as anticoagulant drugs.
Dr. Eric Topol, founder of the Scripps Research Translational Institute and co-author of the recent review, says he is also encouraged by preliminary data in vagus nerve stimulation, which helps control unconscious actions such as breathing and heart rate, to alleviate certain symptoms.
Multiple research teams are also studying transcranial direct current stimulation (tDCS) as a potential treatment. Researchers have already studied whether tDCS devices, which deliver low-intensity electrical currents to the scalp to stimulate the brain, can improve cognition, mental health, and chronic pain. Consumers can purchase a variety of tDCS devices to use at home, although many have not been approved by the FDA.
In a small study that was published online in September 2022 but had not been peer-reviewed, the researchers found that after eight sessions of tDCS, people with Long COVID reported reductions in physical fatigue and depression, although mental fatigue and overall quality of life scores did not improve.
Clinical neurologist and study co-author Dr. Jordi Matias-Guiu says he is planning a longer follow-up study, with patients receiving treatments for three weeks, to see if that leads to better results. “This would need to be confirmed in other clinical trials, but the findings are encouraging,” he says. “This is a technique that could be administered at home, and it is a non-invasive technique with minimal (side effects).”
The list of potential treatments is growing, but the field needs larger, more coordinated research projects, Topol says; for the moment, most of the findings come from small studies that need to be peer-reviewed, scaled-up, and duplicated. RECOVER, the US National Institutes of Health’s billion-dollar Long COVID research project, has begun designing trials of potential treatments, but they have not yet been turned into therapies.
The lack of proven treatments is disappointing, Topol says, but he calls the recent findings on metformin’s potential to prevent long-term COVID “very good news.”
Topol agrees that more studies on metformin are needed, but says he thinks the early findings are promising enough, and that the drug is safe and cheap enough to take personally now if you get sick with COVID-19. “I don’t want to get Long COVID,” says Topol.
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