Prescription
Prescription RequiredCompoundedNaltrexone Capsules
Naltrexone tablets contain a low dose of naltrexone, a medicine that blocks opioid receptors in the brain and body. At low doses, it is often used by healthcare providers to help support weight-management plans and other immune-related conditions, although these uses are not FDA-approved. The tablets are taken by mouth and are made in several dose strengths so providers can tailor therapy to each patient’s needs.
Requires a valid prescription from your provider. Not sure if it's right for you? Ask a pharmacist.
These statements have not been evaluated by the Food and Drug Administration. Compounded products are not FDA-approved and are not intended to diagnose, treat, cure, or prevent any disease. Individual results may vary. This information is for educational purposes only and is not medical advice — always consult your healthcare provider before starting any new treatment.
Clinical information
Medication information for patients and providers.
Use this medicine exactly as your healthcare provider tells you. Swallow the tablet with water at about the same time each day unless told otherwise. If you miss a dose, take it as soon as you remember unless it is almost time for your next dose. Do not take two doses at the same time. Your healthcare provider will decide how long you should stay on treatment.
Naltrexone attaches to opioid receptors for a short time and blocks them. This short block causes your body to rebound and release more of its own natural endorphins after the medicine wears off. Endorphins can improve mood, lower pain signals, and may help control appetite and inflammation. Most people begin to notice benefits within 4–8 weeks, but full effects may take 2–3 months of regular use. Each dose works for about 6–8 hours in the body, yet the endorphin boost can last longer.
Do not use if you are currently taking opioid pain medicines, using opioid street drugs, or are in opioid withdrawal (can cause severe withdrawal symptoms). Do not use if you are allergic to naltrexone or any tablet ingredients. Avoid use if you have acute hepatitis or severe liver failure, as the medicine can stress the liver. Do not use if you are pregnant or breastfeeding unless your provider decides the benefits outweigh the risks. Not for children under 18 unless specifically prescribed by a pediatric specialist.
Serious interaction with all opioid medicines (such as oxycodone, hydrocodone, morphine, codeine cough syrup); do not mix—can cause sudden withdrawal or block pain relief. May lessen the effect of opioid-based diarrhea or cough treatments. Use caution with liver-affecting drugs like isoniazid, methotrexate, acetaminophen over 4,000 mg per day, and some antifungals (ketoconazole) because of added liver stress. Tell your provider if you take warfarin (Coumadin), thioridazine, bupropion, or herbal supplements like kava or valerian, which can raise dizziness or liver side-effect risk. Limit alcohol; heavy drinking increases liver strain.
Very common (more than 1 in 10 people): trouble sleeping, vivid dreams. Common (1–10 in 100 people): nausea, stomach cramps, headache, mild anxiety, tiredness. Uncommon (1–10 in 1,000 people): joint pain, increased heart rate, mild increases in liver enzymes. Rare but serious: severe liver problems (yellow skin or eyes, dark urine), severe allergic reaction (rash, swelling of face or throat). Most mild side effects improve within 1–2 weeks. Contact your provider if side effects are severe, last more than two weeks, or if you notice signs of liver trouble.
Store at controlled room temperature 68–77 °F (20–25 °C) in the original, tightly closed bottle. Keep away from moisture, heat, and direct sunlight. Do not store in bathrooms or near kitchen sinks. Keep out of reach of children and pets. Do not use tablets past the expiration date printed on the label. Return unused or expired tablets to a pharmacy take-back program or mix with used coffee grounds in a sealed plastic bag before throwing in household trash if no take-back is available.
Frequently asked questions.
Do not use any opioid pain medicines (like oxycodone, hydrocodone, or codeine) while taking naltrexone because the tablets block their effect and can cause sudden withdrawal. Non-opioid pain relievers such as acetaminophen or ibuprofen are usually safe, but check with your provider first.
Tell all healthcare workers you take naltrexone. Your surgeon or ER doctor may ask you to stop naltrexone 48–72 hours before planned surgery so opioid pain medicine can work. Never stop on your own without medical advice.
Naltrexone is processed by the liver, so people with active hepatitis or severe liver disease should not use it. If you have any liver history, your provider will check blood tests before and during treatment.
Small social amounts are not likely to cause problems, but heavy drinking puts extra strain on your liver while using this medicine. Limit alcohol and talk with your provider if you drink more than a few drinks per week.
Stopping low-dose naltrexone does not cause withdrawal, but your symptoms may return. Let your provider know before stopping so they can plan the next steps in your treatment.
Keep them in their original bottle, inside a cool, dry bag. Avoid leaving them in a hot car or direct sunlight. If flying, carry them in your hand luggage to prevent extreme temperature changes.
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