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/ comparison

Rapamycin
vs
Metformin

Side-by-side comparison of mechanism, research, dosing, side effects, and pricing.

metabolite

Rapamycin

mTOR inhibitor. Longevity research compound.

Cheapest
$77.24
5mg at Glacier Aminos
See Rapamycin →
metabolite

Metformin

Biguanide. Decades of research on metabolic and longevity outcomes.

Cheapest
$26.05
1000mg at Omegamino
See Metformin →
/ research scoring

Research base

Rapamycin
Research Maturity★★★★★
Evidence Strength★★★★★

FDA approved. Extensive longevity research.

Metformin
Research Maturity★★★★★
Evidence Strength★★★★★

Most-studied metabolic compound. Extensive longevity research.

/ mechanism

How they work

Rapamycin

mTOR inhibitor. Autophagy promotion.

Metformin

AMPK activation. Multiple pleiotropic effects.

/ research dosing

Protocols compared

Rapamycin
Range: 3-6 mg weekly (longevity protocol)
Frequency: Once weekly (pulsed)
Route: Oral on empty stomach
Pulsed weekly dosing (3-6mg) reduces side effects vs daily transplant doses. Empty stomach absorption. Most common longevity research dose: 6mg/week. Monitor lipids, glucose, mTOR-related markers.
Metformin
Range: 500-2000 mg/day
Frequency: 1-2x daily with meals
Route: Oral
Start at 500mg/day with dinner to manage GI adjustment. Titrate up over 4-8 weeks. Extended-release reduces GI side effects. Most common longevity research dose: 1000-1500mg/day.
/ side effects & timeline

What to expect

Rapamycin
Side effects

Common: mouth sores, lipid changes at higher doses.

Timeline

Long-term protocols

Metformin
Side effects

Common: GI adjustment.

Timeline

Long-term

/ pricing

Price comparison

Rapamycin
Lowest price$77.24 (5mg)
Min $/mg$10.37/mg
Avg $/mg$18.73/mg
Max $/mg$30.16/mg
Metformin
Lowest price$26.05 (1000mg)
Min $/mg$0.03/mg
Avg $/mg$0.07/mg
Max $/mg$0.14/mg
/ which to pick

The honest verdict

Pick Rapamycin if: Solo use is standard.

Pick Metformin if: Standard standalone.

Why not both? Some researchers run them together. Check our Interaction Matrix to see if these compounds synergize or work independently.

FOR RESEARCH USE ONLY. Both compounds are intended for laboratory research and not for human consumption.