Low dose naltrexone (LDN) requires a prescription and must be prepared by a compounding pharmacy, so you can’t pick it up off the shelf at a regular drugstore. The typical path is: get a prescription from a doctor or telehealth provider, then have it filled at a compounding pharmacy that ships to your door or operates locally. A 30-day supply generally costs less than $100 out of pocket.
Why You Need a Compounding Pharmacy
Naltrexone is FDA-approved only at 50 mg for treating opioid and alcohol addiction. At that dose, you can get it at any retail pharmacy. But LDN uses doses between 0.1 mg and 4.5 mg, and no manufacturer makes a tablet that small. A compounding pharmacy takes the raw ingredient and prepares it in the exact dose your doctor prescribes.
Standard pharmacies like CVS, Walgreens, and Rite Aid do not compound LDN. Some independent pharmacies have compounding capabilities, but most people use a specialty compounding pharmacy, many of which accept prescriptions electronically and ship nationwide.
How to Get a Prescription
Because LDN is used off-label (there is no FDA-approved use of naltrexone at low doses for any medical condition), not every doctor is familiar with it or willing to prescribe it. You have two main routes.
Your primary care doctor or specialist can write the prescription if they’re open to it. Bring specific information about the condition you want to treat, since many physicians haven’t encountered LDN in their training. Some doctors who treat chronic pain, fibromyalgia, or autoimmune conditions already prescribe it routinely.
If your local provider isn’t an option, telehealth consultations are widely used for LDN. The LDN Research Trust maintains a directory of prescribers, including telehealth providers who do remote consultations specifically for LDN. These appointments are typically straightforward: a video or phone visit where the provider reviews your medical history, discusses whether LDN is appropriate, and sends the prescription directly to a compounding pharmacy.
What It Costs
Insurance rarely covers compounded LDN. The American Academy of Family Physicians notes that naltrexone itself is inexpensive, and out-of-pocket costs for a month’s supply tend to be under $100. Many compounding pharmacies charge between $30 and $60 for a 30-day supply, depending on the formulation and dose. Telehealth consultation fees are separate, typically ranging from $50 to $200 for an initial visit.
Formulations Available
Compounding pharmacies offer LDN in several forms, and the right one depends on your needs and your prescriber’s recommendation.
- Capsules are the most common. The pharmacy fills each capsule with your exact dose plus inactive fillers. Quality varies between pharmacies depending on which fillers they use, so it’s worth asking about ingredients if you have sensitivities to things like lactose or certain dyes.
- Liquid formulations allow very precise dose adjustments, which matters during the titration phase. Liquids compounded in an oil base last 90 to 180 days, while water-based liquids have a much shorter shelf life of 14 to 35 days.
- Sublingual tablets or troches dissolve under the tongue or inside the cheek. These can be useful if you have digestive issues that might affect absorption. A troche (a small wafer) lets you know the full dose has been absorbed once it’s completely dissolved.
- Transdermal creams are applied to the skin. Absorption depends heavily on the base the pharmacy uses, so results can be inconsistent.
How Dosing Works
LDN isn’t a one-size-fits-all medication. While 4.5 mg per day is the most commonly cited dose, research shows effective doses range from as low as 0.1 mg to as high as 5.6 mg, with many patients doing well at 2 mg or less. The right dose appears to be highly individual.
Most prescribers start low and increase gradually. A conservative approach begins at 0.1 mg per day and increases by 0.1 mg every three days. Other providers start at 0.75 mg or 1 mg and adjust from there. This slow titration helps minimize side effects (vivid dreams and mild headaches are the most common early on) and helps identify the lowest effective dose. If no improvement occurs by 6 mg per day, the trial is typically stopped.
This gradual dosing is one reason liquid formulations are popular early in treatment. They make tiny adjustments much easier than swapping capsules every few days.
How LDN Works
At full doses, naltrexone blocks opioid receptors completely. At very low doses, it does something different: it briefly and partially blocks those receptors, which prompts the body to produce more of its own endorphins in response. This increase in natural endorphins helps rebalance the immune system’s inflammatory signaling. The net effect is a reduction in chronic, low-grade inflammation that drives many pain and autoimmune conditions.
In fibromyalgia trials, LDN significantly reduced pain scores compared to placebo and improved overall function as measured by standard fibromyalgia questionnaires. These aren’t enormous effects, but for a medication with minimal side effects and low cost, many patients and providers consider it worth trying.
Important Safety Considerations
LDN blocks opioid receptors, which means it will trigger withdrawal in anyone currently taking opioid medications. You need to be completely off opioids for at least 7 to 10 days before starting LDN. Your prescriber may require a urine test or a naloxone challenge test to confirm you’re opioid-free before writing the prescription. This applies to all opioid painkillers, including tramadol and codeine-containing medications.
This restriction is one of the most important things to discuss honestly with your provider. The exact washout period depends on which opioid you were taking, the dose, and how long you used it.
Choosing a Compounding Pharmacy
Not all compounding pharmacies produce equally consistent results. LDN quality can vary depending on the pharmacy’s equipment, processes, and choice of fillers. A few things to look for: pharmacies that are accredited by the Pharmacy Compounding Accreditation Board (PCAB), those that do third-party potency testing on their compounds, and those with experience specifically preparing LDN. Your prescriber, especially if they work through a telehealth LDN service, will often have a preferred pharmacy they’ve vetted and can recommend.