Lauren Nichols has been suffering from bad health effects since her COVID-19 infection in the spring of 2020. The 34-year-old worker for the U.S. Department of Transportation in Boston has had problems with thinking and attention. She has also suffered from tiredness, seizures, headaches and pain. Last June, Nichols’ doctor suggested she take small amounts of naltrexone, a drug often used to treat alcohol and opioid addiction. The result, she said, was that after more than two years of living in "a thick... cloud...I can actually think clearly." Researchers are studying treatments for the long-lasting effects of COVID infections, known as long COVID. They are excited to learn if naltrexone can offer similar helpful effects to millions of people suffering from health problems months after a coronavirus infection. Reuters studied information from Clinicaltrials.gov and spoke to 12 health researchers about long COVID. The news agency found that there are at least four special studies known as clinical trials that plan to test naltrexone in hundreds of patients with long COVID. Naltrexone is also one of a few treatments to be tested in the U.S. National Institutes of Health's $1 billion RECOVER Initiative. Advisers to the effort say the aim is to learn more about causes of long COVID and to find treatments. Unlike treatments aimed at symptoms caused by COVID damage to organs, such as the lungs, low-dose naltrexone (LDN) may reverse some of the problems that are creating symptoms, they said.