Comparison
Rapamycin vs Testosterone
Side-by-side of Rapamycin and Testosterone. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Rapamycin
Rapamycin for longevity: sirolimus, an mTOR inhibitor with ITP mouse lifespan data. Off-label geroprotective dosing remains investigational.
Testosterone
Testosterone replacement therapy for hypogonadism: TRAVERSE 2023 cardiovascular data, cypionate dosing, body composition gains, Schedule III status.
Effects at a glance
Rapamycin
- •Inhibits mTORC1 signaling by binding FKBP12, reducing protein synthesis and relieving autophagy suppression
- •ITP mouse program reproduced lifespan extension of ~10 to 25% across multiple genetic backgrounds and sexes
- •Mannick trials showed improved influenza vaccine response in elderly adults using analogs of rapamycin
- •PEARL human trial reported acceptable safety at 5 to 10 mg weekly with some functional and lean-mass signals
- •Common dose-limiting adverse effects include stomatitis, acne-like rash, and mildly elevated lipid markers
- •CYP3A4 substrate: grapefruit, ketoconazole, and clarithromycin substantially raise rapamycin exposure
Testosterone
- •Primary androgen; FDA approved for hypogonadism with confirmed deficiency and symptoms
- •Testosterone Trials (2016) showed sexual function and bone density improvements in older hypogonadal men
- •TRAVERSE 2023 (n=5,246) found non-inferiority on MACE versus placebo, with higher AF and PE rates
- •Schedule III controlled substance in US; WADA banned in sport
- •Aromatizes to estradiol; converts to DHT via 5-alpha reductase; both metabolites matter clinically
- •Erythrocytosis (HCT above 54%) affects 5 to 25% of users and is the most common dose-limiting effect
Side-by-side
| Attribute | Rapamycin | Testosterone |
|---|---|---|
| Category | pharmaceutical | hormone |
| Also known as | Sirolimus, Rapamune | TRT, testosterone replacement therapy, testosterone cypionate, testosterone enanthate, Androgel, Testim |
| Half-life (hr) ↗ | 62 | 192 |
| Typical dose (mg) ↗ | 6 | 150 |
| Dosing frequency | weekly (longevity protocols); daily for transplant indication | weekly to twice-weekly (cypionate/enanthate IM or SC); daily (topical, oral); every 3 to 6 months (pellet) |
| Routes | oral | intramuscular, subcutaneous, topical, buccal, subcutaneous (pellet), oral |
| Onset (hr) | 1 | 24 |
| Peak (hr) | 2 | 72 |
| Molecular weight | 914.17 | 288.42 |
| Molecular formula | C51H79NO13 | C19H28O2 |
| Mechanism | Binds FKBP12, and the resulting complex inhibits mTORC1, reducing protein synthesis and autophagy suppression downstream of nutrient and growth-factor signaling. | Androgen receptor agonist driving anabolic gene transcription in muscle, bone, brain, and androgen-sensitive tissue. Aromatized to estradiol and 5-alpha-reduced to DHT, both with distinct downstream effects. |
| Legal status | Prescription only (off-label for longevity) | Schedule III controlled substance (US); WADA banned |
| WADA status | allowed | banned |
| DEA / Rx | Rx only (not a controlled substance) | Schedule III |
| Pregnancy | Not recommended | Category X; contraindicated in pregnancy (virilizing effect on female fetus) |
| CAS | 53123-88-9 | 58-22-0 |
| PubChem CID | 5284616 | 6013 |
| Wikidata | Q410174 | Q150726 |
Safety profile
Rapamycin
Common side effects
- mouth ulcers (stomatitis)
- acne-like rash
- GI upset
- altered lipid panel
- delayed wound healing
Contraindications
- active infection
- severe hepatic impairment
- planned surgery (delayed wound healing)
- pregnancy
- live vaccines within dosing window
Interactions
- strong CYP3A4 inhibitors (ketoconazole, clarithromycin, grapefruit): substantially raises rapamycin levels, toxicity risk(major)
- strong CYP3A4 inducers (rifampin, St John's wort): lowers rapamycin levels, reduced effect(major)
- ACE inhibitors: increased risk of angioedema(moderate)
- live vaccines: reduced vaccine efficacy due to immunosuppression(major)
Testosterone
Common side effects
- erythrocytosis
- acne
- oily skin
- fluid retention
- increased body hair
- fertility suppression
- injection-site reactions
Contraindications
- active prostate cancer
- active breast cancer
- untreated severe sleep apnea
- untreated severe BPH
- uncontrolled heart failure
- polycythemia at baseline
Interactions
- warfarin: may potentiate anticoagulant effect; monitor INR(moderate)
- insulin: may improve insulin sensitivity; monitor glucose in diabetics(moderate)
- 5-alpha reductase inhibitors (finasteride): blocks DHT conversion; reduces some androgen effects(moderate)
- aromatase inhibitors (anastrozole): lowers estradiol; risk of over-suppression(moderate)
Which Should You Take?
Testosterone comes out ahead for most readers on the criteria we weight: 3 catalogued goals, controlled substance, oral dosing, with a Tier-A outcome catalogued. Rapamycin is the right call when one of the conditionals below applies.
- → If your priority is healthspan extension, pick Rapamycin.
- → If your priority is immune support, pick Rapamycin.
- → If your priority is hormonal optimization, pick Testosterone.
- → If your priority is sexual function, pick Testosterone.
Edge case: Testosterone is contraindicated in pregnancy; Rapamycin is the safer pick if that applies.
Default choice: Testosterone. Wider use case, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Rapamycin only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Rapamycin and Testosterone?
Rapamycin and Testosterone differ in category (pharmaceutical vs hormone), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Rapamycin or Testosterone?
Rapamycin half-life is 62 hours; Testosterone half-life is 192 hours.
Can you stack Rapamycin with Testosterone?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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