Comparison
Low-Dose Naltrexone vs Sermorelin
Side-by-side of Low-Dose Naltrexone and Sermorelin. 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.
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.
Sermorelin
Sermorelin peptide therapy uses a 29-amino-acid GHRH analog to raise endogenous GH. Dosing, half-life, sermorelin vs ipamorelin, and safety.
Effects at a glance
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
Sermorelin
- •Synthetic 29-amino-acid GHRH fragment; FDA approved 1997 for pediatric GH deficiency as Geref
- •Voluntarily discontinued by Serono in 2008 for commercial reasons; not safety-related
- •Compounded by 503A/503B pharmacies for off-label adult anti-aging and body-composition use
- •Produces physiologic pulsatile GH release; ~10 to 20 minute plasma half-life
- •Standard anti-aging clinic protocol: 200 to 500 mcg subcutaneously pre-bed, often with ipamorelin
- •Banned by WADA under S2 (peptide hormones, growth factors)
Side-by-side
| Attribute | Low-Dose Naltrexone | Sermorelin |
|---|---|---|
| Category | pharmaceutical | peptide |
| Also known as | LDN, naltrexone (low dose) | Sermorelin acetate, GRF 1-29, Geref, GHRH (1-29) NH2 |
| Half-life (hr) ↗ | 4 | 0.25 |
| Typical dose (mg) ↗ | 4.5 | 0.3 |
| Dosing frequency | once daily, typically at bedtime | 1-2x daily |
| Routes | oral | subcutaneous |
| Onset (hr) | 1 | 0.25 |
| Peak (hr) | 1.5 | 0.5 |
| Molecular weight | 341.4 | 3357.88 |
| Molecular formula | C20H23NO4 | C149H246N44O42S |
| Mechanism | 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. | Synthetic 29-amino-acid GHRH fragment that binds the GHRH receptor on pituitary somatotrophs to stimulate endogenous pulsatile GH synthesis and release while preserving the GH-IGF-1 negative feedback loop. |
| Legal status | Off-label compounded prescription (naltrexone is FDA approved for opioid and alcohol use disorder at 50 mg) | FDA approved 1997 (Geref, pediatric GHD); voluntarily discontinued by Serono 2008; compounded by 503A/503B pharmacies for off-label adult use; banned by WADA |
| WADA status | allowed | banned |
| DEA / Rx | Rx only (not a controlled substance) | Rx only via compounding (no controlled-substance schedule) |
| Pregnancy | Insufficient data; not routinely recommended | Category C (historical labeling); not recommended in pregnancy |
| CAS | 16590-41-3 | 86168-78-7 |
| PubChem CID | 5360515 | 16129617 |
| Wikidata | Q426444 | Q416620 |
Safety profile
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)
Sermorelin
Common side effects
- injection-site pain or irritation
- transient flushing
- headache
- vivid dreams (pre-bed dosing)
Contraindications
- pregnancy
- active malignancy
- history of pituitary tumor
- diabetic retinopathy (theoretical)
- untreated hypothyroidism
Interactions
- ipamorelin: synergistic GH release via parallel GHRH and ghrelin pathways; standard anti-aging clinic pairing(minor)
- CJC-1295: pharmacologically redundant (both GHRH-pathway); typically not stacked(minor)
- insulin: sustained GH can blunt insulin sensitivity over weeks(moderate)
- corticosteroids: blunt GH response; reduce expected efficacy(moderate)
- levothyroxine (untreated hypothyroidism): untreated hypothyroidism blunts GH response; correct thyroid first(moderate)
Which Should You Take?
Low-Dose Naltrexone and Sermorelin score evenly on the criteria we weight (goal breadth, legal accessibility, evidence depth). The conditionals below should drive the decision more than any aggregate score.
- → If your priority is immune support, pick Low-Dose Naltrexone.
- → If your priority is pain modulation, pick Low-Dose Naltrexone.
- → If your priority is growth-hormone axis, pick Sermorelin.
- → If your priority is healthspan extension, pick Sermorelin.
Edge case: If you cannot self-administer injections, Low-Dose Naltrexone is the only oral option in this pair.
Default choice: either is defensible. Low-Dose Naltrexone edges out on goal breadth + legal accessibility; Sermorelin is the right call if your priority sits in the goals listed 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 Low-Dose Naltrexone and Sermorelin?
Low-Dose Naltrexone and Sermorelin differ in category (pharmaceutical vs peptide), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Low-Dose Naltrexone or Sermorelin?
Low-Dose Naltrexone half-life is 4 hours; Sermorelin half-life is 0.25 hours.
Can you stack Low-Dose Naltrexone with Sermorelin?
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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