Picamilon + Methylnaltrexone
Methylnaltrexone brand name: Relistor.
We found no known interaction between Picamilon and Methylnaltrexone in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the label for Methylnaltrexone states a food rule worth keeping to.
Picamilon and Methylnaltrexone
We checked these two against our interaction database. Here is what we found.
No Known Interaction Found
We did not find a documented interaction between Methylnaltrexone and Picamilon in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.
If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.
Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.
Picamilon safety at a glance
Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Why No Interaction Is Listed for Methylnaltrexone
Interactions in our licensed database are recorded against drug classes, not just single drug names. Methylnaltrexone is filed under a single classification — cytochrome p450 2d6 (cyp2d6) inhibitors. Picamilon has documented interactions with 1 drug class — the most serious being niacin (moderate) — and none of Methylnaltrexone’s classifications are among them.
Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.
Picamilon Does Interact With Other Medications
Picamilon has 3 moderate known drug interactions in our database — Methylnaltrexone isn’t one of them. If you take anything else, check it against the full list below.
Check Another of Your Medications Against Picamilon
We haven’t checked that one against Picamilon yet — ask our pharmacists directly.
Covers the 2,830 medications we’ve checked against Picamilon. Pick one to open its full report.
Some Methylnaltrexone Products Have a Food Rule — Picamilon Should Not Break It
At least one FDA label for a product containing Methylnaltrexone says to take it on an empty stomach. Most supplements — Picamilon included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Methylnaltrexone on its own and move Picamilon to a meal later in the day.
This may not be true of your version. Food instructions belong to the product, not the ingredient: two Methylnaltrexone products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.
o In patients with chronic non-cancer pain and OIC, take RELISTOR tablets with water on an empty stomach at least 30 minutes before the first meal of the day.
From the Dosage and Administration section of the FDA label we read for Methylnaltrexone — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›
A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.
See Every Supplement That Interacts With Methylnaltrexone
This page covers Picamilon only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Methylnaltrexone page lists 3 supplements it has a documented interaction with, worst first, each one explained.
The most serious there right now: Fever Bark (moderate), Iboga (moderate) and Yohimbe (moderate).
By severity: 3 moderate.
From our pharmacist’s overview on the Methylnaltrexone page
“If you take methylnaltrexone (Relistor) for opioid-induced constipation, the supplement list to know is short: three ingredients, all rated moderate, none major. Yohimbe, fever bark, and iboga are all cleared by the same liver enzyme, CYP2D6, and methylnaltrexone can slow that enzyme, letting their active compounds build up in your blood.”
Reviewed by 2 · Jul 18, 2026
Taking Picamilon as Part of a Dietary Supplement Product? Check It for Interactions
We hold 135 real supplement products containing Picamilon, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Picamilon. Even though Picamilon itself has no known interaction with Methylnaltrexone, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:
Where Picamilon and Methylnaltrexone Sit Against Everything Else
Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.
#425 of 1,452 supplements looked up here in the last 7 days
#2,278 of 2,830 medications looked up here in the last 7 days
Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.
Where does our data come from?
- Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
- Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Picamilon reference on this page ↓
- Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Picamilon and Methylnaltrexone records this page draws on were last updated June 22, 2026.
- What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
About Picamilon
What is Picamilon?
- Anxiety and stress
- Mental focus and cognition
- Low mood
- Migraine or headache
- Fatigue and energy
Picamilon is a synthetic compound made by joining niacin (vitamin B3) and GABA, originally developed in the former Soviet Union as a prescription drug. It is sold in some countries as a supplement for anxiety, focus, and mood, but high-quality human evidence is very limited, and U.S. regulators have stated it does not qualify as a legal dietary supplement ingredient. Talk to a pharmacist or doctor before using it.
Synthetic compound (not from a plant) · Capsules, tablets, powder
An interaction check asks whether these two react with each other — it does not ask whether Picamilon is a good idea for someone in your situation. Here is what our Picamilon record says about it on its own.
Picamilon: dosing
There is no officially established or standardized dose of picamilon for supplement use, and quality control of products is uncertain.If a product is available to you, follow the directions on the label and do not exceed them.
From our Picamilon monograph — the full record covers uses, side effects and every documented interaction.
About Methylnaltrexone
What Is Methylnaltrexone Used For?
Brand name: Relistor
Methylnaltrexone, sold as Relistor, treats opioid-induced constipation (OIC) — constipation caused by opioid pain medications. Both Relistor tablets and Relistor injection are approved for adults with chronic non-cancer pain, including those with pain related to a prior cancer or its treatment who do not need frequent opioid dose increases.
Relistor injection is also approved for adults with advanced illness or active cancer pain who require increasing opioid doses as part of palliative care.
Other Drugs & Picamilon
Browse every other medication we’ve checked against Picamilon — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
3 interactions
No interaction 2,826 drugs checked — show the list
We also checked Picamilon against these medications and found no known interaction in our sources. Open any page to confirm.
- Apixaban ›
- Levothyroxine ›
- Amlodipine ›
- Methylphenidate ›
- Warfarin ›
- Sertraline ›
- Testosterone ›
- Losartan Potassium ›
- Metoprolol ›
- Ivermectin ›
- Aspirin ›
- Rivaroxaban ›
- Rosuvastatin ›
- Escitalopram ›
- Acetaminophen ›
- Tadalafil ›
- Clopidogrel ›
- Atorvastatin ›
- Abemaciclib ›
- Docusate ›
- Hydroxyurea ›
- Valacyclovir ›
- Ibuprofen ›
- Methamphetamine ›
- Sumatriptan ›
- Semaglutide ›
- Tirzepatide ›
- Warfarin Sodium ›
- Prednisone ›
- Propranolol ›
- Lisdexamfetamine ›
- Bupropion ›
- Metformin ›
- Amoxicillin ›
- Lisinopril ›
- Bendamustine ›
- Acyclovir ›
- Amitriptyline ›
- Methotrexate ›
- Doxycycline ›
- Fluoxetine ›
- Acetaminophen, Codeine ›
- Amphetamine ›
- Lamotrigine ›
- Pregabalin ›
- Gabapentin ›
- Azithromycin ›
- Dextroamphetamine ›
- Isotretinoin ›
- Methylene Blue ›
- Clonazepam ›
- Omeprazole ›
- Amlodipine Besylate ›
- Quetiapine ›
- Duloxetine ›
- Letrozole ›
- Buspirone ›
- Naproxen ›
- Citalopram ›
- Ciprofloxacin ›
Showing the 60 most looked-up of 2,826 medications checked with no known interaction — see the full Picamilon list.
Picamilon References
The 3 references that drive our Picamilon monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.
- Avula B, Chittiboyina AG, Sagi S, et al. Identification and quantification of vinpocetine and picamilon in dietary supplements sold in the United States. Drug Test Anal. 2016;8(3-4):334-43. PubMed
- Vishnevskii EL, Guseva NB. Validation of the treatment of the neurogenic bladder in children with myelodysplasia using pikamilon [abstract only]. Urol Nefrol (Mosk) 1998;(2):27-30.
- Kolomoitseva EM, Ermakova VN, Abdulkadyrova MZh. Results of pikamilon use in the treatment of patients with open-angle glaucoma [abstract only]. Vestn Oftalmol 1994;110(4):4-7.
Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
Taking Picamilon and Methylnaltrexone Together: Common Questions
Is it safe to take Picamilon with Methylnaltrexone?
Should I take Picamilon and Methylnaltrexone at the same time of day?
How was the Picamilon and Methylnaltrexone combination checked?
Does Picamilon interact with any other medications?
Does Methylnaltrexone interact with any supplements?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.