Low-Dose Naltrexone (LDN)
Low-Dose Naltrexone (1.5–4.5 mg at bedtime, vs. 50 mg addiction dose) transiently blocks opioid receptors for 4–6 hours, causing a rebound upregulation of endogenous opioids (endorphins) and opioid growth factor (OGF). OGF-OGF receptor signalling is a critical regulator of cell proliferation — LDN restores this to inhibit cancer cell growth. Used extensively in integrative oncology for haematological cancers, pancreatic cancer, and autoimmune conditions.
Mechanism of Action
At bedtime, LDN transiently blocks μ-opioid and OGF receptors during peak endorphin production (midnight–4 am). The rebound after receptor blockade causes 2–3x upregulation of endorphins and OGF. OGF (met-enkephalin) binding to its nuclear receptor inhibits DNA synthesis and cell proliferation in cancer cells. Additionally, LDN increases NK cell and T-regulatory cell activity through toll-like receptor 4 (TLR4) modulation.
Cancer Types Studied
Protocols & Dosing
Standard LDN Protocol
Start at 1.5 mg at bedtime (10 pm–midnight). Increase to 3 mg after 2 weeks, then 4.5 mg after 4 weeks if tolerated. Take on empty stomach. Compounding pharmacy required — not commercially available at 4.5 mg.
Titration Sensitive Protocol
Start at 0.5 mg daily, increase by 0.5 mg every 2 weeks to 4.5 mg. Use for chemosensitive patients and those with autoimmune comorbidities.
NIH / PubMed Research
Links open on PubMed (National Library of Medicine). Research is ongoing — results may not reflect clinical use.
Cautions & Contraindications
- MUST stop 3+ days before ANY opioid pain medication surgery — blocks all opioid analgesia
- Cannot be used with opioid pain medications (morphine, codeine, fentanyl) — causes acute withdrawal
- Requires compounding pharmacy prescription — not available as standard drug at therapeutic dose
- May cause vivid dreams or mild insomnia initially — usually resolves in 2–4 weeks
- Discuss with oncologist — avoid during immunotherapy (checkpoint inhibitor) treatment
- Not for patients currently using opioids for pain management
Informational only. Not medical advice. Consult your oncologist before starting any alternative or integrative therapy.