Comparison
Hexarelin vs Vitamin D3 + K2
Side-by-side of Hexarelin and Vitamin D3 + K2. 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.
Hexarelin
Hexarelin peptide is a ghrelin-receptor hexapeptide. Largest acute GH pulse in the GHRP class, highest cortisol and prolactin lift, CD36 cardioprotective sign.
Vitamin D3 + K2
Vitamin D3 K2 supplement profile: cholecalciferol at 1000-4000 IU/day corrects deficiency, MK-7 directs calcium to bone, away from arteries.
Effects at a glance
Hexarelin
- •Synthetic hexapeptide GHS-R1a agonist; produces the largest acute GH pulse of the synthetic GHRP class
- •Independent CD36 signaling produces cardioprotective effects in rodent ischemia models, GH-independent
- •Pronounced tachyphylaxis: GH response attenuates over 2 to 4 weeks of daily dosing
- •More cortisol and prolactin elevation than GHRP-2 or ipamorelin
- •Anecdotal protocols use 100 to 200 mcg subcutaneously 1 to 2 times daily for 2 to 4 week pulses
- •Banned by WADA under S2; advanced through phase 2 trials but never reached registration
Vitamin D3 + K2
- •Reduces non-vertebral fractures 10-20% in older adults at 800 IU/day or above when combined with calcium
- •VITAL trial showed neutral results on primary CV and cancer endpoints at 2000 IU/day over 5 years
- •Vitamin D supplementation reduces respiratory infection incidence ~10-20% in deficient populations
- •K2 MK-7 has 72-hour plasma half-life vs 1-2 hours for MK-4; once-daily dosing is sufficient
- •Synergy hypothesis is largely preclinical; dedicated combination RCTs are limited
- •Daily dosing outperforms bolus dosing for immune and infection outcomes
Side-by-side
| Attribute | Hexarelin | Vitamin D3 + K2 |
|---|---|---|
| Category | peptide | supplement |
| Also known as | Examorelin, EP-23905, His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2 | cholecalciferol + menaquinone, D3/K2, vitamin D3 with MK-7 |
| Half-life (hr) ↗ | 1 | 360 |
| Typical dose (mg) ↗ | 0.1 | 0.05 |
| Dosing frequency | 1-2x daily | daily with a fat-containing meal |
| Routes | subcutaneous, intranasal, intravenous | oral |
| Onset (hr) | 0.25 | 24 |
| Peak (hr) | 0.5 | 168 |
| Molecular weight | 887.04 | 384.64 |
| Molecular formula | C47H58N12O6 | C27H44O (D3); C46H64O2 (MK-7) |
| Mechanism | Hexapeptide agonist of GHS-R1a producing acute GH release with cortisol and prolactin co-elevation. Independent CD36 binding produces GH-independent cardioprotective signaling in preclinical models. | D3 converts to calcidiol then calcitriol, activating the vitamin D receptor (VDR) to increase intestinal calcium absorption and modulate immune and bone gene transcription. K2 carboxylates osteocalcin and matrix Gla protein, directing calcium toward bone and inhibiting vascular calcification. |
| Legal status | Not FDA approved; advanced through phase 2 trials in EU but never registered; research-use-only grey market; banned by WADA | Dietary supplement (global) |
| WADA status | banned | allowed |
| DEA / Rx | Not scheduled (research chemical) | Not scheduled |
| Pregnancy | Insufficient data; not recommended | Recommended at standard doses for fetal bone development; consult clinician at higher doses |
| CAS | 140703-51-1 | 67-97-0 |
| PubChem CID | 3037387 | 5280795 |
| Wikidata | Q5743550 | Q139347 |
Safety profile
Hexarelin
Common side effects
- water retention
- vivid dreams
- head pressure or flushing
- transient lethargy
- tingling at injection site
- moderate hunger
Contraindications
- pregnancy
- active malignancy
- history of pituitary tumor
- uncontrolled diabetes
- prolactin-sensitive states
Interactions
- CJC-1295: synergistic GH release; accelerates tachyphylaxis if used continuously(minor)
- sermorelin: additive GH release via parallel GHRH and ghrelin pathways(minor)
- insulin: sustained GH can blunt insulin sensitivity over weeks(moderate)
- corticosteroids: amplify cortisol load; blunt GH response(moderate)
Vitamin D3 + K2
Common side effects
- GI upset at high doses
- headache (rare)
- hypercalcemia (only at sustained very high D3 doses)
Contraindications
- hypercalcemia
- sarcoidosis
- active hyperparathyroidism
- warfarin therapy (K2 component requires stable intake)
Interactions
- warfarin: K2 component can affect anticoagulation; maintain stable intake and inform anticoagulation clinic(moderate)
- thiazide diuretics: additive calcium retention; hypercalcemia risk with high-dose D3(moderate)
- digoxin and calcium channel blockers: additive effects from D3-induced hypercalcemia(moderate)
- glucocorticoids: reduced vitamin D efficacy and bone effects(moderate)
- cholestyramine and orlistat: bind fat-soluble vitamins; separate dosing by 2 to 4 hours(moderate)
Which Should You Take?
Vitamin D3 + K2 comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-A outcome catalogued. Hexarelin is the right call when one of the conditionals below applies.
- → If your priority is growth-hormone axis, pick Hexarelin.
- → If your priority is post-training recovery, pick Hexarelin.
- → If your priority is bone density, pick Vitamin D3 + K2.
- → If your priority is healthspan extension, pick Vitamin D3 + K2.
Edge case: If you want to avoid research-only / gray-market sourcing, Vitamin D3 + K2 is the more accessible choice.
Default choice: Vitamin D3 + K2. Lower friction to source, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Hexarelin 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 Hexarelin and Vitamin D3 + K2?
Hexarelin and Vitamin D3 + K2 differ in category (peptide vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Hexarelin or Vitamin D3 + K2?
Hexarelin half-life is 1 hours; Vitamin D3 + K2 half-life is 360 hours.
Can you stack Hexarelin with Vitamin D3 + K2?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper