Naltrexone 0.5mg
Generic For: Low Dose Naltrexone
Naltrexone 0.5mg, often called Low Dose Naltrexone (LDN), is a capsule form of the opioid antagonist naltrexone prescribed at a fraction of the standard dose. At full strength, naltrexone is FDA-approved for alcohol use disorder and opioid dependence; at low doses it is prescribed off-label for conditions such as chronic pain and fibromyalgia. After review of your prescription by a licensed provider, your medication ships from a licensed U.S. pharmacy.
Compare all Naltrexone options →
Select Quantity *
30-day supply · $1.50/capsule
How It Works
- Select your medication
- Licensed providers review & prescribe
- Our licensed U.S. pharmacists fill your prescription
- Delivered to you as soon as the next day
Price: $45.00
HSA/FSA Eligible*Doctor visit fee & delivery cost not included in price. Refills at provider discretion.
Pharmacist Support
Fast Shipping
Licensed U.S. Pharmacy
Buy Naltrexone 0.5mg (Low Dose Naltrexone) Online
An opioid antagonist prescribed off-label at low doses for chronic pain, fibromyalgia, and inflammatory conditions
Naltrexone 0.5mg Quick Facts
| Drug class | Opioid antagonist |
|---|---|
| Treats | Chronic pain (off-label), fibromyalgia (off-label), alcohol use disorder (full dose), opioid dependence (full dose) |
| Form | Capsule |
| Typical dosing | Take 1 capsule by mouth daily |
| Prescription required | Yes — prescription only |
What Is Naltrexone 0.5mg?
Naltrexone is an opioid antagonist that blocks opioid receptors in the brain. At the standard 50mg dose, it is FDA-approved to help treat alcohol use disorder and to prevent relapse in opioid dependence. Naltrexone 0.5mg, known as Low Dose Naltrexone (LDN), is a much smaller compounded dose that some providers prescribe off-label for chronic pain, fibromyalgia, and certain inflammatory or autoimmune conditions. Low-dose use is investigational and should be guided by your prescriber.
What Does Naltrexone 0.5mg Treat?
Chronic pain (off-label)
Fibromyalgia (off-label)
Inflammatory and autoimmune conditions (off-label)
Alcohol use disorder (FDA-approved at standard 50mg dose)
Opioid dependence, relapse prevention (FDA-approved at standard 50mg dose)
Naltrexone 0.5mg Dosage
Low-dose (off-label): 0.5mg by mouth once daily; titrate per prescriber, commonly up to 4.5mg daily.
FDA-approved standard dose (alcohol/opioid use disorder): 50mg by mouth once daily.
Take exactly as directed by your prescriber.
Your prescriber will determine the dose and duration that are right for you. Always follow the directions on your prescription label.
Naltrexone 0.5mg Side Effects
Common side effects
- Nausea
- Headache
- Vivid dreams or sleep disturbances
- Dizziness
- Fatigue
- Anxiety or nervousness
- Decreased appetite
Serious side effects
Stop taking this medication and seek medical attention right away if you experience:
- Signs of liver injury (dark urine, yellowing of skin or eyes, severe abdominal pain)
- Severe allergic reaction (rash, swelling, difficulty breathing)
- Depression or suicidal thoughts
- Precipitated opioid withdrawal (agitation, sweating, vomiting)
- Injection-site or severe skin reactions
Warnings & Interactions
Do not use if currently taking opioid medications or in acute opioid withdrawal
Blocks the effect of opioid pain medicines; opioid-containing products will not work as expected
Must be opioid-free for 7–14 days before starting (per prescriber guidance)
Use caution in liver disease; hepatotoxicity has been reported at high doses
Attempting to overcome the opioid blockade can cause life-threatening overdose
Tell your provider if you are pregnant, planning pregnancy, or breastfeeding
Low-dose use is off-label and requires prescriber supervision
Tell your prescriber about all medications, supplements, and health conditions before starting naltrexone 0.5mg.
Sources & References
Talk to U.S.-Based Support
Our licensed pharmacy team in Boca Raton, Florida — real people, no overseas call centers.