# Naltrexone Overview Naltrexone is an opioid receptor antagonist. In high doses, it can be used to block the effects of opioids to treat opioid use disorder. At low doses, it appears to have an anti-inflammatory effect on the brain (microglial cells) and the rest of the body (mast cells). This has been shown in clinical trials to reduce pain in patients with fibromyalgia. Many patients with ME/CFS have also found this medication useful for pain, brain fog, mood and fatigue (though the studies are more limited in this population). The optimal dose of Low Dose Naltrexone (LDN) is unknown and probably varies from patient to patient. The tiny doses recommended for ME/CFS and fibromyalgia need to be specially compounded by a compounding pharmacy or by the patient at home. Home compounding is easy and low cost. [Altartp.com](https://altarp.com/how-to-prepare-low-dose-naltrexone-ldn/) has detailed instructions. I also include detailed instructions at the end of this article. # Cost The most common cost of LDN from a compounding pharmacy is about $1 per capsule. Skip’s Pharmacy quoted me $24-$34 for a #30 capsule prescription depending on the strength. I believe that they can ship anywhere in the US. In contrast, compounding at home costs less than $5 per month. # Dose The following are my recommended titration schedules for each compounding method. ### LDN From a Compounding Pharmacy Day 1-7: One 1.5 mg capsule daily Day 8+: One 3 mg capsule daily After 6 weeks, consider increasing the dose to 4.5 mg daily. ### LDN Compounded At Home Dissolve a 50 mg tablet of naltrexone in 50 mL of water to make a 1 mg/mL solution. Day 1-7: 1 mL daily Day 8-14: 2 mL daily Day 15+: 3 mL daily After 6 weeks, consider increasing the dose to 4 mL daily. If the patient fails an initial trial, you can consider the more complex titration regimen suggested by Marcus et. al. [Norman J. Marcus, Lexi Robbins, Aya Araki, Edward J. Gracely, Theoharis C. Theoharides. Effective Doses of Low-Dose Naltrexone for Chronic Pain - An Observational Study. *Journal of Pain Research*. 2024;VOL(ISSUE);1273–1284.10.2147/JPR.S451183](https://pubmed.ncbi.nlm.nih.gov/38532991/) # Side Effects and Risks of LDN LDN is best taken at bedtime. However, if the patient develops insomnia or vivid dreams it can be taken in the morning instead. Insomnia and nausea are the most common side effects. The patient should be aware that most doctors are unfamiliar with the use of naltrexone to treat ME/CFS and fibromyalgia. I have seen patients written off as “drug seekers” when they go to the ER or convenient care for pain control because they have naltrexone on their drug list. The use of low dose naltrexone in patients taking opioid pain medications is not well studied. Unlike high dose naltrexone, low dose naltrexone is not contraindicated but may affect how well the opioid medication works. I don’t have any personal experience combining these medications. # How to Compound Naltrexone at home ## Supplies - 1 naltrexone tablet, 50 mg - A measuring cup able to measure out 50 mL (such as this one) - 3 mL (pediatric dose) syringe (you may be able to obtain one for free if you ask your local pharmacist). - ~ A 10 mL syringe may be useful for larger doses - A small container, at least 50 mL volume, with airtight lid (such as this one) - Distilled water ## Instructions 1. Cut or break the tablet (50 mg naltrexone) in half and place in the container. 2. Measure out 50 mL of distilled water into the measuring up and pour into the container. This will make a solution with a strength of 1 mg per mL. 3. Close the container and shake it. The medicine will dissolve quickly but the added ingredients in the tablet will remain, making the solution cloudy until settling to the bottom. 4. Place the lid on the container and put it in the refrigerator for storage. 5. The solution will remain good for 60 days after which point it should be tossed and a new solution made. 6. To take the medicine, shake the solution and then draw up the prescribed dose into the syringe. For example, if you need 1 mg you should draw up 1 mL. If you need 3.5 mg you should draw up 3.5 mL. 7. Squirt the correct amount into your mouth and swallow. It will be bitter. If desired, you can chase it with juice or something else to reduce the bitterness.