Comparison
Ipamorelin vs Low-Dose Naltrexone
Side-by-side of Ipamorelin and Low-Dose Naltrexone. 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.
Ipamorelin
Ipamorelin peptide benefits: selective ghrelin-receptor GHRP, 200 to 300 mcg dosage, GH pulse without cortisol or prolactin rise, CJC-1295 stack vs sermorelin.
Low-Dose Naltrexone
Low dose naltrexone at 1.5 to 4.5 mg, one-tenth the 50 mg addiction dose. Compounded Rx. Small trials in fibromyalgia, Crohn's, Hashimoto's.
Effects at a glance
Ipamorelin
- •Pentapeptide GHS-R1a agonist with the cleanest selectivity profile in the GHRP class
- •Minimal cortisol and prolactin elevation at standard doses (substantially less than GHRP-2 or hexarelin)
- •~2 hour plasma half-life, longest of the synthetic GHRPs
- •Largest human safety database (~600 participants in Helsinn's postoperative ileus phase 2)
- •Standard pairing for CJC-1295 no-DAC at 200 to 300 mcg subcutaneously 2 to 3 times daily
- •Banned by WADA under S2; never reached registration despite phase 2b development
Low-Dose Naltrexone
- •Off-label use at 1.5 to 4.5 mg, roughly one-tenth the FDA-approved 50 mg addiction-treatment dose
- •Proposed mechanisms include brief opioid receptor blockade triggering rebound endogenous opioid release, plus TLR4 antagonism
- •Compounded prescription only; insurance rarely covers; cash prices 20 to 80 USD per month
- •Younger 2013 reported ~30% pain reduction in fibromyalgia at 4.5 mg in a small crossover trial
- •Smith 2011 reported endoscopic improvement in active Crohn's disease (n=40 placebo-controlled)
- •Vivid dreams affect 20 to 40% in first 2 weeks; manageable by switching to morning dosing
Side-by-side
| Attribute | Ipamorelin | Low-Dose Naltrexone |
|---|---|---|
| Category | peptide | pharmaceutical |
| Also known as | NNC 26-0161, Aib-His-D-2-Nal-D-Phe-Lys-NH2 | LDN, naltrexone (low dose) |
| Half-life (hr) ↗ | 2 | 4 |
| Typical dose (mg) ↗ | 0.2 | 4.5 |
| Dosing frequency | 2-3x daily | once daily, typically at bedtime |
| Routes | subcutaneous, intravenous | oral |
| Onset (hr) | 0.25 | 1 |
| Peak (hr) | 1 | 1.5 |
| Molecular weight | 711.86 | 341.4 |
| Molecular formula | C38H49N9O5 | C20H23NO4 |
| Mechanism | Selective GHS-R1a agonist that stimulates pulsatile GH release with minimal cortisol or prolactin co-activation. Suppresses hypothalamic somatostatin and stimulates pituitary somatotrophs. | Brief mu-opioid receptor antagonism proposed to trigger compensatory upregulation of endogenous opioids; secondary TLR4 antagonism on microglia and immune cells contributes to anti-inflammatory effect. |
| Legal status | Not FDA approved; advanced through phase 2b in postoperative ileus before discontinuation; research-use-only grey market; banned by WADA | Off-label compounded prescription (naltrexone is FDA approved for opioid and alcohol use disorder at 50 mg) |
| WADA status | banned | allowed |
| DEA / Rx | Not scheduled (research chemical) | Rx only (not a controlled substance) |
| Pregnancy | Insufficient data; not recommended | Insufficient data; not routinely recommended |
| CAS | 170851-70-4 | 16590-41-3 |
| PubChem CID | 11338566 | 5360515 |
| Wikidata | Q1666741 | Q426444 |
Safety profile
Ipamorelin
Common side effects
- injection-site irritation
- vivid dreams
- transient mild head pressure
- occasional headache
Contraindications
- pregnancy
- active malignancy
- history of pituitary tumor
- uncontrolled diabetes
Interactions
- CJC-1295: synergistic GH release via parallel GHRH and ghrelin pathways; standard pairing(minor)
- sermorelin: additive GH release; functionally similar pairing to CJC-1295 with shorter GHRH half-life(minor)
- insulin: sustained GH can blunt insulin sensitivity over weeks(moderate)
- corticosteroids: blunt GH response; reduce expected efficacy(moderate)
Low-Dose Naltrexone
Common side effects
- vivid dreams
- sleep disruption
- headache
- mild GI upset
- fatigue (early)
Contraindications
- concurrent opioid use
- acute hepatitis or liver failure
- opioid dependence
- pregnancy (insufficient data)
Interactions
- opioid analgesics (oxycodone, morphine, codeine): blocks analgesic effect; precipitates withdrawal in dependent users(major)
- tramadol: blocks opioid component of analgesia(major)
- thyroid hormone replacement: may alter dose requirements after immune modulation; monitor TSH(minor)
Which Should You Take?
Low-Dose Naltrexone comes out ahead for most readers on the criteria we weight: 2 catalogued goals, prescription-only, oral dosing, with a Tier-A outcome catalogued. Ipamorelin is the right call when one of the conditionals below applies.
- → If your priority is growth-hormone axis, pick Ipamorelin.
- → If your priority is post-training recovery, pick Ipamorelin.
- → If your priority is immune support, pick Low-Dose Naltrexone.
- → If your priority is pain modulation, pick Low-Dose Naltrexone.
Edge case: If you cannot self-administer injections, Low-Dose Naltrexone is the only oral option in this pair.
Default choice: Low-Dose Naltrexone. Wider use case, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Ipamorelin 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 Ipamorelin and Low-Dose Naltrexone?
Ipamorelin and Low-Dose Naltrexone differ in category (peptide vs pharmaceutical), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Ipamorelin or Low-Dose Naltrexone?
Ipamorelin half-life is 2 hours; Low-Dose Naltrexone half-life is 4 hours.
Can you stack Ipamorelin with Low-Dose Naltrexone?
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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