Ergothioneine + Cysteamine
Cysteamine brand name: Cystadrops.
We found no known interaction between Ergothioneine and Cysteamine 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 Cysteamine states a food rule worth keeping to.
Ergothioneine and Cysteamine
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 Cysteamine and Ergothioneine 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.
Worth understanding: our licensed dataset holds no drug-interaction record for Ergothioneine at all — not against Cysteamine, and not against any other medication we track. This verdict therefore rests on the absence of any recorded data, not on research that looked at this combination and found nothing. We cannot rule an interaction out.
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.
Ergothioneine safety at a glance
Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Some Cysteamine Products Have a Food Rule — Ergothioneine Should Not Break It
At least one FDA label for a product containing Cysteamine says to take it with food. If you take Ergothioneine on an empty stomach out of habit, keep them separate — and take Cysteamine with a meal where the label says to.
This may not be true of your version. Food instructions belong to the product, not the ingredient: two Cysteamine 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.
If unable to take PROCYSBI without eating, take with food but limit the amount of food to approximately 4 ounces (½ cup) 1 hour before through 1 hour after administration.
From the Dosage and Administration section of the FDA label we read for Cysteamine — 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.
Taking Ergothioneine as Part of a Dietary Supplement Product? Check It for Interactions
We hold 10 real supplement products containing Ergothioneine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Ergothioneine. Even though Ergothioneine itself has no known interaction with Cysteamine, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:
Where Ergothioneine and Cysteamine 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.
#1,171 of 1,452 supplements looked up here in the last 7 days
#2,494 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 Ergothioneine reference on this page ↓
- Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Ergothioneine and Cysteamine 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 Ergothioneine
What is Ergothioneine?
- Antioxidant support
- Healthy aging and longevity
- Cellular protection
- Cognitive and brain health
- General wellness
Ergothioneine is a naturally occurring amino acid–like compound (an antioxidant) found mostly in mushrooms and made by certain fungi and bacteria. Early laboratory studies suggest it may help protect cells from oxidative stress, but solid human evidence for any specific health benefit is still limited. It appears generally well tolerated, but if you are pregnant, breastfeeding, or taking other medicines, check with your pharmacist or doctor first.
Naturally found in certain mushrooms and other foods; produced by some fungi and bacteria · Capsules, tablets, powders, and as a nutrient in mushroom-based foods
An interaction check asks whether these two react with each other — it does not ask whether Ergothioneine is a good idea for someone in your situation. Here is what our Ergothioneine record says about it on its own.
Ergothioneine: dosing
There is no officially established dose for ergothioneine supplements. Doses used in research have varied, and a standard recommended amount has not been set.The safest approach is to follow the dosing on the product label and not exceed it. You can also increase your intake naturally by eating more mushrooms.
From our Ergothioneine monograph — the full record covers uses, side effects and every documented interaction.
About Cysteamine
What Is Cysteamine Used For?
Brand name: Cystadrops
Cysteamine treats cystinosis, a rare inherited disease in which a substance called cystine accumulates inside cells and damages organs — especially the kidneys, eyes, and other tissues over time.
Cystagon (oral capsule) and Procysbi (oral delayed-release capsule and oral powder) are each used to treat nephropathic cystinosis — the kidney-affecting form of the disease — in children and adults. Cystadrops and Cystaran are eye drops used to treat corneal cystine crystal deposits (cystine crystals that form on the surface of the eye) in patients with cystinosis.
Other Drugs & Ergothioneine
Browse every other medication we’ve checked against Ergothioneine — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
No interaction 2,829 drugs checked — show the list
We also checked Ergothioneine against these medications and found no known interaction in our sources. Open any page to confirm.
- Apixaban ›
- Levothyroxine ›
- Amlodipine ›
- Methylphenidate ›
- Warfarin ›
- Sertraline ›
- Losartan Potassium ›
- Testosterone ›
- Ivermectin ›
- Abemaciclib ›
- Aspirin ›
- Metoprolol ›
- Acetaminophen ›
- Rosuvastatin ›
- Rivaroxaban ›
- Escitalopram ›
- Clopidogrel ›
- Atorvastatin ›
- Tadalafil ›
- Docusate ›
- Tirzepatide ›
- Ibuprofen ›
- Methamphetamine ›
- Hydroxyurea ›
- Warfarin Sodium ›
- Valacyclovir ›
- Sumatriptan ›
- Semaglutide ›
- Prednisone ›
- Lisdexamfetamine ›
- Propranolol ›
- Metformin ›
- Amitriptyline ›
- Amoxicillin ›
- Lisinopril ›
- Isotretinoin ›
- Methotrexate ›
- Amlodipine Besylate ›
- Bendamustine ›
- Bupropion ›
- Amphetamine ›
- Fluoxetine ›
- Doxycycline ›
- Acyclovir ›
- Azithromycin ›
- Lamotrigine ›
- Pregabalin ›
- Dextroamphetamine ›
- Gabapentin ›
- Acetaminophen, Codeine ›
- Quetiapine ›
- Clonazepam ›
- Levothyroxine, Liothyronine ›
- Naproxen ›
- Omeprazole ›
- Letrozole ›
- Methylene Blue ›
- Duloxetine ›
- Buspirone ›
- Citalopram ›
Showing the 60 most looked-up of 2,829 medications checked with no known interaction — see the full Ergothioneine list.
Ergothioneine References
The 2 references that drive our Ergothioneine 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.
- Benson KF, Ager DM, Landes B, Aruoma OI, Jensen GS. Improvement of joint range of motion (ROM) and reduction of chronic pain after consumption of an ergothioneine-containing nutritional supplement. Prev Med. 2012;54 Suppl:S83-9. PubMed
- Smith E, Ottosson F, Hellstrand S, et al. Ergothioneine is associated with reduced mortality and decreased risk of cardiovascular disease. Heart 2019. pii: heartjnl-2019-315485. PubMed
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 Ergothioneine and Cysteamine Together: Common Questions
Is it safe to take Ergothioneine with Cysteamine?
Should I take Ergothioneine and Cysteamine at the same time of day?
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.