Comparison
Low-Dose Naltrexone vs Selank
Side-by-side of Low-Dose Naltrexone and Selank. 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.
Selank
Selank peptide benefits: tuftsin analog heptapeptide, intranasal anxiolytic and nootropic. Russian clinical data, dosing, half-life, 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
Selank
- •Synthetic heptapeptide analog of tuftsin developed in Russia in the 1990s
- •Approved in Russia for generalized anxiety disorder and asthenic conditions
- •Russian RCTs report anxiolytic effects comparable to medazepam without sedation or dependence
- •Modulates GABAergic and serotonergic signaling and BDNF expression in preclinical models
- •Most commonly administered intranasally; subcutaneous use is anecdotal
- •No Western-validated trials; not FDA approved; research-use-only outside Russia
Side-by-side
| Attribute | Low-Dose Naltrexone | Selank |
|---|---|---|
| Category | pharmaceutical | peptide |
| Also known as | LDN, naltrexone (low dose) | TP-7, Tuftsin analog |
| Half-life (hr) ↗ | 4 | 0.5 |
| Typical dose (mg) ↗ | 4.5 | 0.4 |
| Dosing frequency | once daily, typically at bedtime | 2-3x daily (intranasal) |
| Routes | oral | intranasal, subcutaneous |
| Onset (hr) | 1 | 0.25 |
| Peak (hr) | 1.5 | 1 |
| Molecular weight | 341.4 | 751.85 |
| Molecular formula | C20H23NO4 | C33H57N11O9 |
| 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. | Modulates GABAergic, serotonergic, and dopaminergic signaling. Increases BDNF expression in hippocampal neurons in preclinical models. Modulates enkephalin levels and immune cytokine signaling via tuftsin-like activity. |
| Legal status | Off-label compounded prescription (naltrexone is FDA approved for opioid and alcohol use disorder at 50 mg) | Approved as a prescription anxiolytic in Russia; not FDA approved; research-use-only grey market in most other jurisdictions |
| WADA status | allowed | unknown |
| DEA / Rx | Rx only (not a controlled substance) | Not FDA approved; not scheduled; research-chemical status outside Russia |
| Pregnancy | Insufficient data; not routinely recommended | Not recommended; insufficient data |
| CAS | 16590-41-3 | 129954-34-3 |
| PubChem CID | 5360515 | 11765600 |
| Wikidata | Q426444 | Q4416793 |
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)
Selank
Common side effects
- mild nasal irritation (intranasal)
- transient drowsiness (uncommon)
- mild headache
Contraindications
- pregnancy
- lactation
- severe psychiatric disorder (insufficient data)
Interactions
- benzodiazepines: additive anxiolytic effect; potential for over-sedation when stacked(moderate)
- SSRIs: no documented adverse interaction; co-administration described in Russian protocols(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. Selank is the right call when one of the conditionals below applies.
- → If your priority is immune support, pick Low-Dose Naltrexone.
- → If your priority is pain modulation, pick Low-Dose Naltrexone.
- → If your priority is focus or working memory, pick Selank.
- → If your priority is anxiety reduction, pick Selank.
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 Selank 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 Low-Dose Naltrexone and Selank?
Low-Dose Naltrexone and Selank 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 Selank?
Low-Dose Naltrexone half-life is 4 hours; Selank half-life is 0.5 hours.
Can you stack Low-Dose Naltrexone with Selank?
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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