What is Rapamycin?
Rapamycin (also called sirolimus) is a prescription drug taken as a pill. Its main medical purpose is to suppress the immune system so the body doesn’t harm itself through excessive inflammation—especially after organ transplants or in autoimmune conditions. It’s been used safely for decades in organ transplant and cancer patients. More recently, doctors and researchers have been exploring lower doses of rapamycin as a potential treatment for Long COVID, especially when symptoms like fatigue, brain fog, and post-exertional crashes persist.
How Rapamycin Helps with Long COVID
Reduces Inflammation – Many Long COVID symptoms are linked to ongoing inflammation. Rapamycin can calm down this inflammation, possibly easing fatigue, pain, and brain fog.
May Help the Body Clear Residual Virus – Rapamycin activates a process called autophagy, which may help cells clean out lingering viral proteins that may be triggering symptoms.
Improves Blood Flow and Reduces Microclots – Some Long COVID patients have tiny blood clots that block oxygen delivery. Rapamycin may help reduce these, improving circulation and reducing dizziness or shortness of breath.
Supports Brain Function – In animal studies, rapamycin improves memory and brain plasticity. Patients with brain fog may benefit from these effects.
What the research says
Research on rapamycin for Long COVID is still early, but encouraging. Most patients in small trials and case reports have reported improved energy, reduced crashes (PEM), better focus, and fewer symptoms overall. It’s generally well tolerated when used at low weekly doses. Side effects are usually mild and manageable.
Key Literature on Mestinon and Long COVID
Studies Showing Positive Effects
This open‑label observational study tracked 74 patients (ME/CFS n = 42; Long‑COVID n = 32) who took 3–6 mg rapamycin weekly for 90 days. 72.5 % of patients reported clear improvement in fatigue, post-exertional crashes, and daily functioning. No serious side effects were reported.
This transplant‑registry cohort looked at kidney transplant patients who got COVID. Those taking rapamycin or similar drugs had much milder COVID illness, suggesting potential protection against longer-term complications like Long COVID.
Study Showing No Apparent Effect
This randomized controlled trial tested rapamycin during acute COVID infection. While it was safe, it did not significantly improve outcomes in hospitalized patients. This study didn’t look at Long COVID specifically.
Articles Discussing Theoretical Benefits
This mechanistic review explains how rapamycin blocks viral replication and overactive immune responses, supporting its use in long-term viral illnesses.
This hypothesis paper outlines why rapamycin may help reverse the metabolic and immune dysfunction seen in Long COVID.
Ongoing & Registered Trials (Results Pending)
Mount Sinai Low‑Dose Rapa Trial – Double‑blind RCT (NCT06960928), 80 adults, weekly 1→4 mg for 12 weeks.
Final Thoughts
Rapamycin shows real promise for Long COVID. While it’s still considered experimental, early data suggest that about two-thirds of patients may experience meaningful symptom relief. Some patients report that improvements last even after stopping the medication, while others find that symptoms begin to return weeks after discontinuation. This suggests that Rapamycin may help manage ongoing inflammation or immune dysfunction but doesn’t necessarily eliminate the root cause. Whether it directly clears lingering virus from the body remains unknown. For patients whose symptoms return, one possible strategy is to combine Rapamycin with antivirals, particularly if viral persistence is suspected. As this is a prescription medication, its use can only be guided by a medical professional.