Drug & supplement interaction

Toothed Clubmoss + Stavudine

Stavudine brand name: Zerit.

No Known Interaction

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated July 2026 · Pair last verified Sep 27, 2026

The bottom line No known interaction

We found no known interaction between Toothed Clubmoss and Stavudine 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

Toothed Clubmoss and Stavudine

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 Stavudine and Toothed 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.

Toothed Clubmoss safety at a glance

Toothed Clubmoss overall Use caution May cause nervous-system and digestive side effects, and product quality varies widely.

Pregnancy Avoid Not enough safety information; avoid during pregnancy.

Breastfeeding Avoid Not enough safety information; avoid while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Stavudine and Toothed Clubmoss? Ask Dr. Brian Staiger, PharmD, BCPS directly ›

How we checked

Why No Interaction Is Listed for Stavudine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Stavudine is filed under 2 classifications — nucleoside reverse transcriptase inhibitors (nrtis), oral drugs. Toothed Clubmoss has documented interactions with 2 drug classes — the most serious being anticholinergic drugs (moderate) and cholinergic drugs (moderate) — and none of Stavudine’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

Toothed Clubmoss Does Interact With Other Medications

Toothed Clubmoss has 219 moderate known drug interactions in our database — Stavudine 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. Stavudine)

Taking anything else?

Check Another of Your Medications Against Toothed Clubmoss

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

What to actually watch for

What Toothed Clubmoss Itself Has Been Linked To

This is not an interaction — nothing below involves Stavudine. It is the side-effect record for Toothed Clubmoss on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Toothed Clubmoss, this list is the first place to look.

Sweating / Dizziness Additional detail
“No adverse effects have been reported. However, a thorough evaluation of safety outcomes has not been conducted.

Orally, huperzine A, a constituent of toothed clubmoss, can cause dizziness, nausea, and sweating.”

Toothed Clubmoss · Natural Medicines adverse-effect record, reported in nausea and vomiting.
1 source cited

3140. Zhang RW, Tang XC, Han YY, et al. [Drug evaluation of huperzine A in the treatment of senile memory disorders]. Chung Kuo Yao Li Hsueh Pao 1991;12:250-2.
“Orally, huperzine A, a constituent of toothed clubmoss, can cause dizziness and sweating.”

Toothed Clubmoss · Natural Medicines adverse-effect record, reported in vertigo.
1 source cited

3140. Zhang RW, Tang XC, Han YY, et al. [Drug evaluation of huperzine A in the treatment of senile memory disorders]. Chung Kuo Yao Li Hsueh Pao 1991;12:250-2.
Nausea Additional detail
“Orally, huperzine A, a constituent of toothed clubmoss, can cause nausea.”

Toothed Clubmoss · Natural Medicines adverse-effect record, reported in nausea and vomiting.
1 source cited

3140. Zhang RW, Tang XC, Han YY, et al. [Drug evaluation of huperzine A in the treatment of senile memory disorders]. Chung Kuo Yao Li Hsueh Pao 1991;12:250-2.

Everything above comes from the Natural Medicines adverse-effect record for Toothed Clubmoss — expand a row for the licensed statement it rests on. We haven’t matched Stavudine 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 Stavudine.

Everything else you take

See Every Supplement That Interacts With Stavudine

This page covers Toothed Clubmoss only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Stavudine page lists 18 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Glucomannan (moderate) and Guar Gum (moderate).

By severity: 1 major · 8 moderate · 9 minor.

From our pharmacist’s overview on the Stavudine page

“Stavudine (Zerit) fights HIV, and with antiretrovirals the cost of an interaction runs high, since anything that lowers drug levels can let the virus rebound and build resistance. That makes this list one to respect, even though 17 of its 18 entries share a single theme: charcoal, fibers, gums, and mucilage-rich herbs that can blunt ho…”

Reviewed by 2 · Jul 18, 2026

Open the Stavudine interaction page

One more smart check

Taking Toothed Clubmoss as Part of a Dietary Supplement Product? Check It for Interactions

We hold 101 real supplement products containing Toothed Clubmoss, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Toothed Clubmoss. Even though Toothed Clubmoss itself has no known interaction with Stavudine, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Toothed Clubmoss and Stavudine 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 Toothed Clubmoss

Top half

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

29 days ago today

Medication Stavudine

Steady interest

#2,627 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 Toothed Clubmoss reference on this page ↓
Freshness: we automatically re-check this combination every week — this pair was last verified September 27, 2026. The Toothed Clubmoss and Stavudine 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 Dr. Brian Staiger, PharmD, BCPS.

Supplement

About Toothed Clubmoss

What is Toothed Clubmoss?

Memory and cognitive support
Alzheimer's disease and dementia
General brain or 'nootropic' support
Inflammation and pain (traditional use)
Age-related memory loss

Toothed Clubmoss is a moss-like plant best known as the natural source of huperzine A, a compound studied mainly for memory and Alzheimer's disease. Some early research is promising, but the evidence is limited and the supplement is not well standardized or regulated, so quality between products varies. Because it can affect the nervous system, talk with a pharmacist or doctor before using it.

Huperzia serrata · Lycopodiaceae · Whole plant (above-ground parts), the source of huperzine A · Capsules, tablets, powdered extracts; often sold as standardized 'huperzine A' supplements

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

Toothed Clubmoss: dosing

There is no official, standardized dose for Toothed Clubmoss. Most products are labeled by their huperzine A content, often in very small amounts measured in micrograms. Avoid combining different supplements that contain huperzine A.

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

Read the full Toothed Clubmoss monograph & all interactions

Medication

About Stavudine

What Is Stavudine Used For?

Brand name: Zerit

Stavudine is used along with other medications to treat human immunodeficiency virus (HIV) infection. Stavudine is in a class of medications called nucleoside reverse transcriptase inhibitors (NRTIs). It works by decreasing the amount of HIV in the blood. Although stavudine does not cure HIV, it may decrease your chance of developing acquired immunodeficiency syndrome (AIDS) and HIV-related illnesses such as serious infections or cancer. Taking these medications along with practicing safer sex and making other life-style changes may decrease the risk of transmitting (spreading) the HIV virus to other people.

See full Stavudine drug information

Keep checking

Other Drugs & Toothed Clubmoss

Browse every other medication we’ve checked against Toothed 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 Toothed Clubmoss page.

No interaction 2,610 drugs checked — show the list

We also checked Toothed 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 Toothed Clubmoss list.

See the full Toothed Clubmoss interactions page

See every supplement checked against Stavudine, ranked by severity

Evidence & sources

Toothed Clubmoss References

The 3 references that drive our Toothed 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.

Budavari S, ed. The Merck Index. 12th ed. Whitehouse Station, NJ: Merck & Co., Inc., 1996.
Zhang RW, Tang XC, Han YY, et al. [Drug evaluation of huperzine A in the treatment of senile memory disorders]. Chung Kuo Yao Li Hsueh Pao 1991;12:250-2.
Ohba T, Yoshino Y, Ishisaka M, et al. Japanese Huperzia serrata extract and the constituent, huperzine A, ameliorate the scopolamine-induced cognitive impairment in mice. Biosci Biotechnol Biochem. 2015;79(11):1838-44.

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 Toothed Clubmoss and Stavudine Together: Common Questions

Is it safe to take Toothed Clubmoss with Stavudine?

We do not list a known interaction between Toothed Clubmoss and Stavudine. 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 Toothed Clubmoss and Stavudine combination checked?

Interactions in our licensed database are recorded against drug classes. Stavudine is filed under 2 classifications, and Toothed Clubmoss has documented interactions with 2 drug classes — none of Stavudine'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 Toothed Clubmoss interact with any other medications?

Yes. Toothed Clubmoss has 219 documented drug interactions in our database — Stavudine 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 Stavudine interact with any supplements?

Yes. Stavudine has documented interactions with 18 supplements in our database — Toothed Clubmoss is not one of them. The Stavudine 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

Toothed Clubmoss monograph Uses, safety profile, and every drug interaction in one place Stavudine drug information The full plain-English guide to this medication Stavudine supplement interactions Every supplement checked against Stavudine, 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 Stavudine and Toothed 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.