Low dose naltrexone (LDN) is typically started at 1 to 3 mg per day and gradually increased to a target dose of 4.5 mg daily. Because LDN requires compounding at these small doses, the way you take it depends on the form your pharmacy provides and how your body responds during the first few weeks.
Starting Dose and How to Increase
Most prescribers begin LDN at 1 to 1.5 mg per day, though some start as high as 3 mg depending on the condition being treated and individual sensitivity. The goal is to work up to 4.5 mg daily, which is considered the standard therapeutic dose for most people using LDN.
The increase happens gradually. A common approach is to raise the dose by 0.5 to 1.5 mg every one to two weeks, pausing at each level long enough to gauge how you feel. If side effects appear at a new dose, you stay at the previous level for longer before trying again. Some people settle at 3 mg or 3.5 mg because that’s where they get the best response with the fewest side effects. The 4.5 mg ceiling isn’t a requirement for everyone.
When to Take It: Morning vs. Night
There is no single correct time of day to take LDN. The manufacturer of naltrexone does not specify morning or evening dosing, so the best timing comes down to how the medication affects you personally.
Taking it at bedtime works well for many people because LDN briefly blocks opioid receptors, which triggers your body to produce more of its own endorphins overnight. That rebound effect is part of how the drug works. However, some people find that a nighttime dose causes vivid dreams, restlessness, or trouble falling asleep. If that happens, switching to a morning dose often resolves the problem. Conversely, if LDN makes you feel drowsy or slightly dizzy, an evening dose lets those effects pass while you sleep.
The simplest advice: pick a time that fits your routine, then adjust based on what you notice in the first week or two.
Food, Absorption, and Practical Tips
LDN is highly bioavailable regardless of whether you take it with food. It absorbs quickly into the bloodstream in any oral form. That said, taking it on an empty stomach may produce a slightly sharper peak level, so some practitioners suggest avoiding food for 15 to 20 minutes before and after your dose. This is a fine-tuning detail, not a strict rule.
If nausea is an issue, especially in the first days, taking LDN with a small amount of food can help without meaningfully reducing absorption. Nausea, headache, and joint or muscle pain are the most commonly reported side effects and tend to fade as your body adjusts.
Liquid, Capsule, and Other Forms
Because standard naltrexone tablets come in 50 mg (far above the LDN range), your dose needs to be custom-prepared by a compounding pharmacy. LDN comes in several forms, and each one is taken a little differently.
- Liquid: The most common form, especially for people who need fine control over their dose during titration. You measure it with a small oral syringe, similar to what’s used for children’s medicine. A typical single dose is 1 ml. Liquid makes it easy to increase in small increments like 0.5 mg.
- Capsules: Available in pre-measured strengths, commonly 1.5 mg, 3 mg, and 4.5 mg. Capsules are more convenient once you’ve reached a stable dose but less flexible for gradual increases.
- Sublingual drops: Placed under the tongue with a dropper. These are higher concentration than the liquid form and work well for people who have difficulty swallowing capsules.
- Topical cream: An option for people who can’t tolerate any oral form, though it’s less commonly prescribed.
If you’re just starting out, liquid is often the easiest choice because you can adjust by tiny amounts without needing a new prescription each time.
Choosing a Compounding Pharmacy
Not all compounding pharmacies handle LDN the same way, and the fillers used in capsules can matter, particularly if you have food sensitivities or autoimmune conditions. Pharmaceutical-grade fillers are processed through FDA-authorized facilities and offer more consistent particle size, which affects how evenly the active ingredient is distributed in each capsule. Food-grade fillers are sometimes used but may be less consistent.
When you contact a compounding pharmacy, it’s worth asking what filler they use and whether they can accommodate specific requests. Some patients ask for fillers free of common allergens like gluten, lactose, or certain sugars. Pharmacies vary in how flexible they can be due to compounding regulations, so calling ahead saves time.
How Long Before You Notice Results
LDN is not a fast-acting medication. Most people need at least two to three months at their target dose before they can fairly evaluate whether it’s working. Some conditions respond sooner, but the general guidance from experienced clinicians is to allow a minimum of three months before deciding to continue or stop.
For chronic or complex conditions like autoimmune disorders or chronic fatigue, the full benefit may take considerably longer. Some practitioners recommend staying on LDN for 6 to 12 months to fully assess its impact, since maximum improvements for certain conditions may not appear for 8 to 18 months. This long timeline can be frustrating, but incremental changes in sleep quality, energy, or pain levels during the first few months are often early signals that the medication is doing something useful.
How LDN Works Differently Than Standard Naltrexone
Standard naltrexone at 50 mg blocks opioid receptors around the clock, which is why it’s used to reduce alcohol and opioid cravings. At the low doses used in LDN (1 to 4.5 mg), the blockade is brief, lasting only a few hours. When it wears off, the body responds by upregulating its own endorphin production. This rebound increase in endorphins helps modulate the immune system by rebalancing inflammatory signaling and influencing a growth factor pathway involved in cell regulation.
This is why the dose matters so much. Too high and you get prolonged receptor blockade without the rebound. Too low and the signal isn’t strong enough. The 1.5 to 4.5 mg range sits in a narrow window that produces a temporary block followed by a compensatory response, which is the entire basis of the therapy.