Injection
Tirzepatide + B12
A weekly dual-action GLP-1/GIP injection for meaningful weight loss and appetite control, paired with vitamin B12 for energy.
Starting at $198/mo
Weight lossOral medicationImmune modulation
Naltrexone Low-Dose
RxPrescription onlyTaken by mouth · Once a day · 1.5–16 mg · Weight loss · Oral medication · Immune modulation
Starting at $79/mo
Low-dose naltrexone (LDN) used off-label for weight loss and metabolic support. Naltrexone at low doses may reduce inflammation and appetite signaling, supporting modest weight loss.
How many capsules per month?
MonthlyEvery 3 months
30 capsulesper month
You'll receive 30 capsules per month. $99 billed monthly. Cancel anytime.
Real prices from our pharmacy. Longer plans cost less per month and are billed up front. Pause or cancel anytime.
- Off-label use for metabolic and appetite support
- May reduce inflammation linked to weight gain
- Gentle daily oral tablet
Every plan includes
- Personalized, physician-guided plan
- 30 capsules per month, monthly and 3-month
- Dispensed by a US-licensed compounding pharmacy
- Unlimited protocol adjustments and messaging
- Ongoing support and check-ins
- Pause or cancel anytime
- Reviewed by our in-house physicians
- Physician-guided care
- Ongoing, expert support
- 100% online
- Free, discreet shipping
What is Low-Dose Naltrexone?
(LDN, opioid antagonist at low dose)
Naltrexone is approved as a full-dose medication for opioid and alcohol dependence. At low doses (2.5–5 mg daily), it is prescribed off-label for weight loss and metabolic support. The mechanism for weight loss is not fully understood; proposed pathways include reduced inflammation and altered appetite signaling.
- How it is taken
- Taken by mouth
- How often
- Once a day
- Dose range
- 1.5–16 mg
- Form
- Weight loss · Oral medication · Immune modulation
Modest
early-stage evidence; mechanism unclear
Low-dose naltrexone is experimental for weight loss. Some users report modest weight loss and improved mood; others see minimal effect. Mechanism is not well-established. Your physician will monitor your response carefully.
How it works,
week by week.
Day 1
A US-licensed physician reviews your health, metabolism, and why an oral medication may help you. Explains the medication's mechanism and what to expect.
Week 1–2
Start your dose. You may feel appetite changes within days, or changes may take weeks. GI effects (metformin) or mood changes (naltrexone) are possible early on.
Weeks 3–6
Your appetite and eating patterns shift. Fullness comes sooner. Your physician checks in and may adjust your dose based on response and tolerability.
Months 2–3
Steady, gradual weight loss. Metabolism and appetite remain improved. Your physician monitors for any side effects and adjusts dosing.
Beyond
Maintenance: your physician works with you to hold results or adjust as your body changes. Long-term monitoring ensures ongoing safety.
What you may notice,
and when.
Weight loss
steady but modest; depends on diet and activity
Appetite change
reduced hunger or improved fullness is common
Energy and metabolism
gradual improvement with weight loss and diet
Medical oversight
your physician monitors for side effects and efficacy
Individual results vary. Benefits reflect what Zepym Health members commonly report to their physician at check-ins; they are not the results of a clinical trial.
Safety first:
what to know before you start.
Important safety information and common side effects
Oral weight-loss medications (metformin, naltrexone, topiramate) have different safety profiles. Metformin: GI side effects (nausea, diarrhea) common, especially initially; not for severe kidney disease. Naltrexone: generally well-tolerated; headache or dizziness possible. Topiramate: cognitive effects ('topiramate fog', difficulty concentrating, word-finding) in 10–15%; kidney stones possible. All are off-label for weight loss; efficacy and safety are not FDA-approved for this use. Tell your physician about all medications, kidney disease, and any history of kidney stones (topiramate). Stop and seek care for severe GI pain (metformin), severe headache, allergic reactions, or eye pain (topiramate).
The research behind
low-dose naltrexone.
Low-dose naltrexone (usually 4.5 mg) is used off label. No obesity trial of it was found; the weight evidence belongs to a different, higher-dose product, naltrexone with bupropion.
- LDN and weightno trial found
No placebo-controlled trial of low-dose naltrexone for weight in people with obesity was found. Its trials are mostly in other conditions, and a 2026 narrative review says early positive results were rarely replicated.
PubMed search; 2026 narrative review - Naltrexone with bupropiondifferent product
The obesity trials that exist are for naltrexone combined with bupropion, a different and higher-dose product. Its figures are not reproduced here because they were not verified for this page.
PubMed search on naltrexone-bupropion trials - Fibromyalgia pain28.8% vs 18.0%
In 31 women with fibromyalgia, 4.5 mg daily reduced daily pain by 28.8%, against 18.0% on placebo, in a randomized crossover trial (Younger et al., Arthritis & Rheumatism 2013).
Younger et al., Arthritis & Rheumatism 2013
What the studies found
- Lower daily pain in fibromyalgia: 28.8% reduction against 18.0% on placebo at 4.5 mg (Younger et al., Arthritis & Rheumatism 2013, 31 women).
- Better mood and life satisfaction in the same crossover trial, though fatigue and sleep did not improve (Younger et al., 2013).
- No human trial of low-dose naltrexone for weight loss was found; any appetite effect is unproven in people (PubMed search).
No trial in these sources tested low-dose naltrexone for weight. Compounded LDN from pharmacies was not studied, and the combination figures on this page belong to a different product.
What this does not say
- Low-dose naltrexone is used off label; its effect on weight is unknown.
- Naltrexone with bupropion is a separate prescription product with different doses; its results do not transfer.
- The LDN trials that exist are in other diseases, and the fibromyalgia trial had 31 participants; no long-term safety data for weight use was found.
The research
behind it.
Low-dose naltrexone has preclinical and anecdotal support for anti-inflammatory effects and appetite modulation. Human clinical trials for weight loss are limited.
Off-label use is based on mechanism hypothesis and clinical experience. Individual response is highly variable. Your physician explains the limited evidence.
GLP-1 beyond the scale:
what the research showsHeart, kidneys, liver, sleep and joints: the trials, with their numbers and their limits.Read the researchMicrodosing GLP-1:
what we know, and what we don’tLower doses are everywhere online. Here is what has actually been studied, and how our physicians use dose.Read the research
what the research showsHeart, kidneys, liver, sleep and joints: the trials, with their numbers and their limits.Read the researchMicrodosing GLP-1:
what we know, and what we don’tLower doses are everywhere online. Here is what has actually been studied, and how our physicians use dose.Read the research
Getting started
takes a few minutes.
- 1
Connect with a physician
Answer a few questions online and a US-licensed physician reviews your health, history and goals to make sure treatment is right for you. 100% online. No in-person visit required.
- 2
Get your discreet shipment
If approved, your treatment is compounded by a US-licensed, LegitScript-certified pharmacy, inspected for quality, and shipped discreetly to your door.
- 3
Receive continuous support
Start with one goal, then keep building over time. Unlimited physician messaging, easy refills and dose adjustments, all from the Zepym Health app.
Frequently asked questions
Contact supportHow do I take Naltrexone (Low Dose)?
Taken by mouth, once a day, at bedtime. The starting prescription is 1 capsule (1.5 mg) each time. Your physician sets your own dose and it is printed on your label.
What strengths does Naltrexone (Low Dose) come in?
The pharmacy carries 7: 1.5 mg, 3 mg, 4 mg, 5 mg, 6 mg, 8 mg, 16 mg. Your physician chooses which one you get.
How much arrives in each shipment?
30 capsules at the starting strength, shipped to your door from a licensed US pharmacy.
How does low-dose naltrexone help with weight loss?
The exact mechanism is not clear. Proposed pathways include reduced inflammation, improved appetite regulation, and changes in reward signaling. The evidence is early. Your physician will assess your response and adjust based on what works for you.
Why are these off-label?
These medications are FDA-approved for other conditions (diabetes, seizures, addiction) but not specifically for weight loss. Off-label use is legal and common; your physician prescribes based on research and experience.
Which one should I choose?
That depends on your health profile, goals, and what side effects you can tolerate. Metformin is gentlest but least effective. Naltrexone is experimental. Topiramate is moderate. Your physician will recommend based on your individual needs.
Can I combine these with GLP-1 drugs?
Yes, some combinations are used; for example, topiramate plus phentermine. However, combining multiple weight-loss medications requires careful physician oversight.
What if these don't work?
If you see minimal effect after 8–12 weeks, your physician may increase the dose, switch medications, or recommend GLP-1 drugs like semaglutide or tirzepatide for stronger effect.
Low-Dose Naltrexone educational content reviewed by our physician
Scott Nass, MD Doctor of Medicine, board-certified in Family Medicine
Charles R. Drew University and David Geffen School of Medicine at UCLA. Family Medicine residency at Ventura County Medical Center.
More options
in this area.
Injection
Semaglutide + B12
A weekly GLP-1 injection that quiets cravings and supports steady, sustainable weight loss, paired with vitamin B12 for energy.
Starting at $99/mo
Injection
Tirzepatide + Glycine
A weekly dual-action GLP-1/GIP injection for meaningful weight loss and appetite control, paired with glycine for better tolerance.
Starting at $198/mo
Injection
Semaglutide + Glycine
A weekly GLP-1 injection that quiets cravings and supports steady, sustainable weight loss, paired with glycine for better tolerance.
Starting at $99/mo
References
- 1.Metformin and weight loss: a systematic review of non-diabetic use. Obes Surg, 2017
- 2.Topiramate for weight loss: clinical efficacy and safety review. Drugs Today, 2019
Prescription products require an online evaluation with a licensed medical professional who will determine if a prescription is appropriate. Products are compounded by a licensed pharmacy. The FDA has not reviewed or approved compounded products for any use for safety, efficacy, or quality. Compounded medications are not FDA-approved brand-name products.