Drug & supplement interaction

Clubmoss + Interferon Alfa-2b

Interferon Alfa-2b brand names: Rebetron, Intron A, Viraferon.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Clubmoss and Interferon Alfa-2b 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.

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Interaction report

Clubmoss and Interferon Alfa-2b

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 Interferon Alfa-2b and Clubmoss 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.

Clubmoss safety at a glance

Clubmoss overall Use caution It contains toxic alkaloids and has limited safety data, so it should be used carefully if at all.
Pregnancy Possibly Unsafe When used orally; avoid using. Read the full pregnancy detail
Breastfeeding Possibly Unsafe When used orally; avoid using. Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Interferon Alfa-2b and Clubmoss? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Interferon Alfa-2b

Interactions in our licensed database are recorded against drug classes, not just single drug names. Interferon Alfa-2b is filed under 2 classifications — photosensitizing drugs, hepatotoxic drugs. Clubmoss has documented interactions with 3 drug classes — the most serious being acetylcholinesterase (ache) inhibitors (moderate), anticholinergic drugs (moderate) and cholinergic drugs (moderate) — and none of Interferon Alfa-2b’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.

Keep it in perspective

Clubmoss Does Interact With Other Medications

Clubmoss has 219 moderate known drug interactions in our database — Interferon Alfa-2b isn’t one of them. If you take anything else, check it against the full list below.

Moderate 219 No known interaction 2,611 (incl. Interferon Alfa-2b)
Taking anything else?

Check Another of Your Medications Against Clubmoss

Covers the 2,830 medications we’ve checked against Clubmoss. Pick one to open its full report.

What to actually watch for

What Clubmoss Itself Has Been Linked To

This is not an interaction — nothing below involves Interferon Alfa-2b. It is the side-effect record for Clubmoss on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Clubmoss, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • Wheezing Worth acting on Additional detail

    “Orally, no adverse effects have been reported; however, a thorough evaluation of safety outcomes has not been conducted. Additionally, clubmoss contains toxic alkaloids, which could cause serious adverse effects. When fir club moss (Lycopodium selago) is mistaken for clubmoss, cholinergic toxicity has been reported.”

    Clubmoss · Natural Medicines adverse-effect record, reported in asthma.

    2 sources cited
    1. 43721. Cullinan, P., Cannon, J., Sheril, D., and Newman, Taylor A. Asthma following occupational exposure to Lycopodium clavatum in condom manufacturers. Thorax 1993;48(7):774-775. PubMed
    2. 13193. Felgenhauer N, Zilker T, Worek F, Eyer P. Intoxication with huperzine A, a potent anticholinesterase found in the fir club moss. J Toxicol Clin Toxicol 2000;38:803-8.. PubMed

    “Occupational exposure to clubmoss spores, including cases associated with facilities that use the spores to coat condoms, has been reported to cause asthma.”

    Clubmoss · Natural Medicines adverse-effect record, reported in asthma.

    1 source cited
    1. 43721. Cullinan, P., Cannon, J., Sheril, D., and Newman, Taylor A. Asthma following occupational exposure to Lycopodium clavatum in condom manufacturers. Thorax 1993;48(7):774-775. PubMed
  • Sweating / Dizziness / Nausea Additional detail

    “Clubmoss (Lycopodium clavatum) might be mistaken for fir club moss (Lycopodium selago), which contains huperzine A, a constituent with strong inhibitory activity against acetylcholinesterase. In two case reports, fir club moss was mistaken for clubmoss and ingested as tea. This caused cholinergic toxicity with symptoms of sweating, nausea, dizziness, cramping, and slurred speech.”

    Clubmoss · Natural Medicines adverse-effect record, reported in nausea and vomiting.

    1 source cited
    1. 13193. Felgenhauer N, Zilker T, Worek F, Eyer P. Intoxication with huperzine A, a potent anticholinesterase found in the fir club moss. J Toxicol Clin Toxicol 2000;38:803-8.. PubMed

Everything above comes from the Natural Medicines adverse-effect record for Clubmoss — expand a row for the licensed statement it rests on. We haven’t matched Interferon Alfa-2b to its FDA label in our system yet, so we can’t compare its own side-effect list here — the leaflet that comes with your prescription is the authoritative list for Interferon Alfa-2b.

Special populations

Clubmoss in Pregnancy & Breastfeeding

Pregnancy And Lactation Possibly Unsafe

When used orally; avoid using.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

Everything else you take

See Every Supplement That Interacts With Interferon Alfa-2b

This page covers Clubmoss only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Interferon Alfa-2b page lists 57 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Beer (major), Siberian Cocklebur (major), Wine (major), Alfalfa (moderate) and Angelica Archangelica (moderate).

By severity: 3 major · 53 moderate · 1 minor.

From our pharmacist’s overview on the Interferon Alfa-2b page

“People taking interferon alfa-2b (Intron A, Rebetron) are usually treating hepatitis or a cancer, so the liver may already be under strain, and that is exactly where most of this list points. Of the 57 supplements on file, 38 can add to liver stress, and all three major-rated interactions sit in that group: Siberian cocklebur, which ha…”

Reviewed by 2 · Jul 18, 2026

Open the Interferon Alfa-2b interaction page

How much people look this up

Where Clubmoss and Interferon Alfa-2b 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.

Supplement Clubmoss
Steady interest

#736 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Interferon Alfa-2b
Steady interest

#1,575 of 2,830 medications looked up here in the last 7 days

29 days ago today

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 Clubmoss reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Clubmoss and Interferon Alfa-2b records this page draws on were last updated July 10, 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.
Data structure & sourcing designed and verified by .
Supplement

About Clubmoss

What is Clubmoss?

Clubmoss
  • Bladder and kidney complaints
  • Digestive upset
  • Skin irritation and chafing
  • Respiratory problems
  • Used in homeopathy

Clubmoss (Lycopodium clavatum) is a primitive plant with a long history in folk medicine and homeopathy, but there is very little reliable human research to show it works for any health condition. It contains potentially toxic alkaloids, so it should be used with great caution, and people who are pregnant or breastfeeding should avoid it. Talk with a pharmacist or doctor before trying it.

Lycopodium clavatum · Lycopodiaceae · Whole plant and spores · Powdered spores, dried herb, tinctures, teas, homeopathic preparations, capsules

An interaction check asks whether these two react with each other — it does not ask whether Clubmoss is a good idea for someone in your situation. Here is what our Clubmoss record says about it on its own.

Clubmoss: dosing

There is no established, well-studied dose for clubmoss. Because the amount of active and potentially toxic compounds can vary between products and plant sources, a safe dose has not been clearly defined.If you choose to use a clubmoss product, follow the directions on the label and do not exceed them. Homeopathic "Lycopodium" products are extremely diluted and are different from raw herb preparations.

From our Clubmoss monograph — the full record covers uses, side effects and every documented interaction.

Read the full Clubmoss monograph & all interactions
Medication

About Interferon Alfa-2b Injection

What Is Interferon Alfa-2b Injection Used For?

Brand names: Rebetron, Intron A, Viraferon

  • Interferon alfa-2b injection is used to treat a number of conditions.

  • Interferon alfa-2b injection is used

    • alone or in combination with ribavirin (Copegus, Rebetol, Ribasphere) to treat chronic (long-term) hepatitis C infection (swelling of the liver caused by a virus) in people who show signs of liver damage,

    • to treat chronic hepatitis B infection (swelling of the liver caused by a virus) in people who show signs of liver damage,

    • to treat hairy cell leukemia (a white blood cell cancer),

    • to treat genital warts,

    • to treat Kaposi's sarcoma (a type of cancer that causes abnormal tissue to grow on different parts of the body) related to acquired immunodeficiency syndrome (AIDS),

    • to treat malignant melanoma (a cancer that begins in certain skin cells) in certain people who have had surgery to remove the cancer,

    • along with another medication to treat follicular non-Hodgkin's lymphoma (NHL; a slow-growing blood cancer).

  • Interferon alfa-2b is in a class of medications called immunomodulators. Interferon alfa-2b works to treat hepatitis C virus (HCV) and hepatitis B virus (HBV) by decreasing the amount virus in the body. Interferon alfa-2b may not cure hepatitis B or hepatitis C or prevent you from developing complications from these infections such as cirrhosis (scarring) of the liver, liver failure, or liver cancer. It also may not prevent the spread of hepatitis B or C to other people. It is not known exactly how interferon alfa-2b works to treat cancer or genital warts.

See full Interferon Alfa-2b Injection drug information
Keep checking

Other Drugs & Clubmoss

Browse every other medication we’ve checked against Clubmoss — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
219Moderate
0Minor
2,610No known interaction
219 Moderate 2,610 No interaction
Moderate

219 interactions

Showing 60 of 219 moderate interactions — see all 219 on the Clubmoss page.

No interaction 2,610 drugs checked — show the list

We also checked Clubmoss against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,610 medications checked with no known interaction — see the full Clubmoss list.

See the full Clubmoss interactions page
See every supplement checked against Interferon Alfa-2b, ranked by severity
Evidence & sources

Clubmoss References

The 3 references that drive our Clubmoss 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.

  1. Felgenhauer N, Zilker T, Worek F, Eyer P. Intoxication with huperzine A, a potent anticholinesterase found in the fir club moss. J Toxicol Clin Toxicol 2000;38:803-8.. PubMed
  2. Orhan, I., Terzioglu, S., and Sener, B. Alpha-onocerin: an acetylcholinesterase inhibitor from Lycopodium clavatum. Planta Med. 2003;69(3):265-267.
  3. Cullinan, P., Cannon, J., Sheril, D., and Newman, Taylor A. Asthma following occupational exposure to Lycopodium clavatum in condom manufacturers. Thorax 1993;48(7):774-775. 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.

Pharmacist Counseling Corner

Taking Clubmoss and Interferon Alfa-2b Together: Common Questions

Is it safe to take Clubmoss with Interferon Alfa-2b?
We do not list a known interaction between Clubmoss and Interferon Alfa-2b. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Clubmoss and Interferon Alfa-2b combination checked?
Interactions in our licensed database are recorded against drug classes. Interferon Alfa-2b is filed under 2 classifications, and Clubmoss has documented interactions with 3 drug classes — none of Interferon Alfa-2b's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Clubmoss interact with any other medications?
Yes. Clubmoss has 219 documented drug interactions in our database — Interferon Alfa-2b is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Interferon Alfa-2b interact with any supplements?
Yes. Interferon Alfa-2b has documented interactions with 57 supplements in our database — Clubmoss is not one of them. The Interferon Alfa-2b interaction page linked on this page lists every one, ranked by severity.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Where next

Keep Exploring

Clubmoss monograph Uses, safety profile, and every drug interaction in one place Interferon Alfa-2b Injection drug information The full plain-English guide to this medication Interferon Alfa-2b supplement interactions Every supplement checked against Interferon Alfa-2b, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 3 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Interferon Alfa-2b and Clubmoss?

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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.