Naltrexone
NAL-trehk-sohn
Category
Compound type
Phase / Status
FDA approved for addiction treatment
Standard Dose
As directed
Half-life
Plasma elimination
Route(s)
Oral, Injectable or Topical
Research Stage
Regulatory approval granted; post-market monitoring ongoing.
Overview
Naltrexone is an opioid receptor antagonist, meaning it blocks receptors that opioids normally activate. Because of that, it can precipitate withdrawal if you still have opioids in your system, so clinicians typically use an opioid-free window and, when needed, a naloxone challenge.
Plain-language summary
Naltrexone is an opioid receptor antagonist, meaning it blocks receptors that opioids normally activate. Because of that, it can precipitate withdrawal if you still have opioids in your system, so clinicians typically use an opioid-free window and, when needed, a naloxone challenge.
Administration Routes
- Oral
- Injectable
- Topical
Also known as
Mechanisms
Opioid receptor antagonist
Detailed mechanism
Naltrexone is a competitive antagonist at mu, kappa, and delta opioid receptors, blocking endogenous and exogenous opioid ligands from producing their usual downstream effects (such as dopamine release in reward pathways and respiratory depression). At standard clinical doses (50 mg), this blockade reduces the reinforcing effects of opioids and alcohol, supporting abstinence in addiction treatment. At very low doses (1.5–4.5 mg, sometimes called LDN), a transient receptor blockade is hypothesized to produce a rebound upregulation of endogenous opioid tone and possible immune-modulatory effects, though evidence for these off-label applications remains exploratory.
Safety
Side effects
- Nausea
- Headache
- Anxiety
- Liver toxicity
Reported benefits
- Reduces opioid cravings
- Alcohol dependence treatment
- Immune modulation (LDN)
Safety profile
Consult medical professional before use
Clinical trials
See research status
Structure
Verified structure
Naltrexone
Exact 2D structure can be rendered from a PubChem-backed canonical SMILES string.
- Chemical Formula
- C20H23NO4
- Molecular Weight
- 341.4 g/mol
- CAS Number
- 16590-41-3
- InChIKey
- DQCKKXVULJGBQN-XFWGSAIBSA-N
Stack Context
No stack data available.
References
- 1View source
Naltrexone prescribing information - boxed warnings and opioid-free precautions (FDA drug label)
2022
- 2View source
Naltrexone and coping skills therapy for alcohol dependence: a controlled study (Archives of General Psychiatry)
1992
- 3View source
Low-dose naltrexone for fibromyalgia: a pilot study showing symptom reduction (Pain Medicine)
2009
This profile summarizes research literature for education only. It is not medical advice, and it does not diagnose, treat, or recommend a dose. Consult a qualified professional before changing a protocol.