Old Drugs, New Hope for Brain Fog and Long COVID Fatigue

July 27, 2026 - 19:09

Two common drugs, one used for constipation and another for depression, are being tested as potential treatments for the lingering cognitive and physical symptoms of long COVID. Early trial results suggest these existing medications might offer relief for the brain fog and exhaustion that plague millions of patients.

The first drug, a type of antidepressant, is being studied specifically for its effect on severe fatigue. Researchers found that patients who took the medication reported a significant reduction in energy drain compared to those on a placebo. The theory is that the drug may help regulate the immune system's overreaction, which is thought to contribute to long COVID symptoms.

The second drug, typically prescribed for constipation, is being examined for its ability to clear brain fog. In a small study, participants who took the medication showed improvements in memory, concentration, and processing speed. Scientists believe the drug works by reducing inflammation in the brain, which can be triggered by the lingering virus.

Both trials are still in early phases, but the results are encouraging because these are already approved, low-cost medications. This means they could be prescribed quickly if larger studies confirm the benefits. For patients who have struggled with limited treatment options, these findings offer a concrete path forward. More research is needed to determine the right dosages and which patients will benefit most, but the idea of repurposing old drugs for new uses is gaining momentum in the fight against long COVID.