What is naltrexone used for?

Naltrexone is FDA-approved to support treatment of alcohol use disorder and to help prevent relapse in opioid dependence. At low doses such as 5mg, providers sometimes prescribe it off-label for chronic pain, fibromyalgia, and related conditions.

What is Low Dose Naltrexone (LDN)?

Low Dose Naltrexone refers to naltrexone taken at much lower strengths (typically 1–5mg) than the standard 50mg dose. It is prescribed off-label, and research on its uses is ongoing, so it should only be taken under a provider's guidance.

Do I need a prescription for naltrexone 5mg?

Yes. Naltrexone is a prescription-only medication in the United States. A licensed provider must evaluate whether it is appropriate for you and issue a valid prescription before we can dispense it.

Is naltrexone an opioid or addictive?

No. Naltrexone is an opioid antagonist, meaning it blocks opioid receptors rather than activating them. It is not a controlled substance and is not habit-forming.

Can I take naltrexone if I'm using opioid pain medication?

No. Naltrexone blocks opioids and can trigger sudden, severe withdrawal if opioids are in your system. You generally must be opioid-free for 7–14 days before starting, as directed by your provider.

How does ordering and shipping work?

After you place your order, a licensed provider or pharmacist reviews your prescription and health information. Once approved, your medication is dispensed by our licensed U.S. pharmacy and shipped directly to you in discreet packaging.

What are the most common side effects of naltrexone?

The most common side effects include nausea, headache, dizziness, fatigue, and vivid dreams. Many are mild and improve over time, but contact your provider if side effects persist or worsen.

Naltrexone 5mg

Name: Naltrexone 5mg
Brand: All Family Pharmacy
SKU: naltrexone-5mg
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Generic For: Low Dose Naltrexone

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Naltrexone is an opioid antagonist that is FDA-approved to support treatment of alcohol use disorder and opioid dependence. At the 5mg strength, often called Low Dose Naltrexone (LDN), it is frequently prescribed off-label for conditions such as chronic pain and fibromyalgia. After a licensed provider reviews your prescription, your order ships from a licensed U.S. pharmacy.

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Buy Naltrexone 5mg (Low Dose Naltrexone) Online

An opioid antagonist prescribed for alcohol use disorder, opioid dependence, and — at low doses — chronic pain conditions

Medically reviewed by David Paul Mackarey, RPh, Pharmacist-in-Charge

Naltrexone 5mg Quick Facts

Drug class	Opioid antagonist
Treats	Alcohol use disorder, opioid dependence, chronic pain (off-label)
Form	Capsule
Typical dosing	Take 1 capsule by mouth daily
Prescription required	Yes — prescription only

What Is Naltrexone 5mg?

Naltrexone is a prescription medication that blocks opioid receptors in the brain. At standard doses (50mg), it is FDA-approved to help reduce cravings in alcohol use disorder and to block the effects of opioids in people recovering from opioid dependence. The 5mg capsule, commonly called Low Dose Naltrexone (LDN), is a lower-strength form that providers sometimes prescribe off-label for conditions involving chronic pain or inflammation. Because it is not an opioid and is not habit-forming, naltrexone works differently from many other medications used for these conditions.

What Does Naltrexone 5mg Treat?

Alcohol use disorder
Opioid dependence (relapse prevention after detoxification)
Chronic pain (off-label, low dose)
Fibromyalgia (off-label, low dose)
Inflammatory and autoimmune-related symptoms (off-label, low dose)

Naltrexone 5mg Dosage

FDA-labeled: 50 mg by mouth once daily for alcohol use disorder or opioid dependence.
Low dose (off-label): Take 1 capsule (5 mg) by mouth once daily, or 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 5mg Side Effects

Common side effects

Nausea
Headache
Dizziness
Fatigue
Trouble sleeping
Anxiety or nervousness
Stomach pain or cramps
Vivid dreams

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)
New or worsening depression or suicidal thoughts
Severe injection-site or skin reactions
Precipitated opioid withdrawal symptoms

Warnings & Interactions

Do not use if currently taking opioids or in acute opioid withdrawal — can cause sudden, severe withdrawal
Must be opioid-free for 7–14 days before starting (per prescriber guidance)
Blocks opioid pain medications; carry medical identification and inform all providers
Use caution in liver disease; liver monitoring may be recommended
Attempting to overcome the opioid blockade with large opioid doses can cause life-threatening overdose
Tell your provider if you are pregnant, planning pregnancy, or breastfeeding
Do not use if you have had an allergic reaction to naltrexone

Tell your prescriber about all medications, supplements, and health conditions before starting naltrexone 5mg.