Low Dose Naltrexone (LDN) for Arachnoiditis: What It Is, How It Works, and What to Expect
- EveBlackburn
- 2 days ago
- 3 min read
Low Dose Naltrexone — commonly called LDN — has become one of the most talked-about treatments in the Arachnoiditis community. Patients share it in groups, physicians are increasingly familiar with it, and research continues to grow. But what is it, how does it actually work, and is it right for you?
This article covers the essentials in plain language.
What Is Naltrexone?
Naltrexone is an FDA-approved medication most commonly prescribed at 50mg doses to treat opioid and alcohol addiction. At that dose it works by blocking opioid receptors in the brain.
But at much lower doses — typically 0.5mg to 4.5mg — something different happens. Rather than blocking opioid receptors continuously, LDN creates a brief, temporary blockade that triggers a rebound response. The body responds to that brief blockade by producing more of its own natural endorphins and by modulating the immune system.
That rebound effect is where the therapeutic benefit comes from.
Important note: If you are currently taking opioid medications, LDN and ULDN require careful management. Standard LDN can interfere with opioid pain relief. Ultra Low Dose Naltrexone (ULDN) at 0.5mg to 1.0mg twice daily is the version Dr. Tennant recommended for patients already on opioids — it works through a different mechanism and does not block opioid receptors in the same way.
How LDN Works
LDN works through two distinct pathways:
1. Endorphin modulation The temporary opioid blockade signals the body to upregulate its own endorphin production. Higher endorphin levels support pain reduction and immune function. This is the primary mechanism behind LDN's pain-relieving effects.
2. Anti-inflammatory action LDN reduces neuroinflammation by inhibiting cytokine production and modulating glial cell activity. Glial cells are central to the inflammatory process in Adhesive Arachnoiditis — they are what produce the neuroinflammation that drives the disease. LDN's anti-inflammatory effect can begin within 30 minutes of dosing.
Together these two mechanisms make LDN relevant to two of the three components of the Tennant Protocol — pain control and inflammation suppression.
Where LDN Fits in the Tennant Protocol
Dr. Tennant included LDN and ULDN in his Three Component Protocol but with an important distinction based on severity:
For mild or new cases: LDN 0.5 to 1.0mg twice daily is listed as an add-on option for Component 1 (pain control)
For patients not on opioids: Standard LDN is an option for neuroinflammation suppression
For patients on opioids: ULDN is the appropriate version — it avoids interfering with opioid analgesia
LDN is not a standalone treatment for AA. It works best as part of a comprehensive protocol.
Dosing and Starting
LDN must be obtained from a compounding pharmacy as it is not available commercially at low doses. Your physician will need to write a prescription specifying the dose.
General starting guidance:
Begin at a low dose — typically 0.5mg — and increase gradually
Standard LDN range is 1.5mg to 4.5mg daily, taken at night
ULDN range is 0.5mg to 1.0mg twice daily
Liquid formulations allow easier dose adjustment than capsules
Capsule fillers matter — dextrose, sucrose, or ginger are preferred to minimize side effects
Common early side effects:
Vivid dreams or sleep disturbance — usually temporary and often resolves within a few weeks
Mild nausea — typically passes as the body adjusts
Most patients who experience initial side effects find they resolve within the first two to four weeks.
What Patients Report
LDN has a substantial and growing body of patient experience behind it. Many Arachnoiditis patients report meaningful reductions in baseline pain, reduced flare frequency, and improved energy and mood. Others find limited benefit.
Response varies significantly based on disease severity, individual biology, and whether LDN is being used alongside a full protocol or in isolation. Severe AA patients tend to report more modest results than those with milder presentations.
It is worth trying — it has a favorable safety profile, is relatively inexpensive, and the downside risk is low. But go in with realistic expectations and give it adequate time. Most clinicians recommend a minimum trial of three months before drawing conclusions.
Finding a Prescribing Physician
Not all physicians are familiar with LDN. If your current doctor is unfamiliar with it, the LDN Research Trust maintains resources for both patients and physicians including clinical references you can bring to an appointment.
Our Physician Directory also lists doctors with experience treating Arachnoiditis who may be more receptive to prescribing LDN as part of a comprehensive protocol.
Further Reading and Resources
LDN Research Trust — comprehensive research, clinical trials, and patient resources
This article is for educational purposes only and does not constitute medical advice. Always consult a qualified physician before making changes to your treatment plan. See our Disclaimer.