Rapamycin + Metformin Interaction

⚠️ RESEARCH-BASED INTERACTION DATA — NOT COMPREHENSIVE.

Interaction Type: synergistic | Evidence Level: moderate

Rapamycin and metformin converge on mTOR/AMPK signaling from opposite directions — rapamycin directly inhibits mTORC1 while metformin activates AMPK, which indirectly suppresses mTORC1. Together they achieve broader pathway coverage.

Mechanism of Interaction

Rapamycin allosterically inhibits mTORC1 via FKBP12 binding. Metformin inhibits mitochondrial Complex I → increases AMP:ATP ratio → activates AMPK → phosphorylates TSC2 and Raptor, suppressing mTORC1 through a distinct mechanism. The combination provides complementary mTOR suppression plus AMPK-mediated metabolic benefits (improved insulin sensitivity, fatty acid oxidation) that may offset rapamycin's metabolic side effects (glucose intolerance, dyslipidemia).

Clinical Relevance

Preclinical data in mice shows the rapamycin + metformin combination extends lifespan more than either agent alone. Metformin may mitigate rapamycin-induced glucose intolerance. Both are individually in longevity clinical trials.

Recommendations

• Monitor fasting glucose and HbA1c closely — opposing metabolic effects
• Consider metformin as an adjunct to manage rapamycin-induced dyslipidemia
• Weekly rapamycin + daily metformin is the most studied combination schedule
• Renal function monitoring essential (metformin renal clearance)

Relevant Conditions

• Longevity / healthspan optimization
• Cancer prevention
• Metabolic syndrome