Drug & supplement interaction

Calea Zacatechichi + Interferon Alfa-2b

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

No Known Interaction
The bottom line No known interaction

We found no known interaction between Calea Zacatechichi 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

Calea Zacatechichi 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 Calea Zacatechichi 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.

Calea Zacatechichi safety at a glance

Calea Zacatechichi overall Use caution It has a long folk-use history but little modern safety data, and it can cause nausea and vomiting.
Pregnancy Avoid There is no reliable safety data, so it is best avoided during pregnancy.
Breastfeeding Avoid There is no reliable safety data, so it is best avoided while breastfeeding.

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

Still wondering about combining Interferon Alfa-2b and Calea Zacatechichi? 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. Calea Zacatechichi has documented interactions with 2 drug classes — the most serious being antidiabetes drugs (minor) and cns depressants (minor) — 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

Calea Zacatechichi Does Interact With Other Medications

Calea Zacatechichi has 334 minor 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.

Taking anything else?

Check Another of Your Medications Against Calea Zacatechichi

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

What to actually watch for

What Calea Zacatechichi Itself Has Been Linked To

This is not an interaction — nothing below involves Interferon Alfa-2b. It is the side-effect record for Calea Zacatechichi on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Calea Zacatechichi, this list is the first place to look.

  • Drowsiness Additional detail

    “There is currently a limited amount of information on the adverse effects of Calea zacatechichi. Observations in healthy volunteers indicate that it is bitter tasting and may cause vomiting and somnolence.”

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

    “In healthy volunteers, a methanol extract of Calea zacatechichi produces somnolence with short periods of light sleep and decreases in deep slow-wave sleep and rapid eye movement (REM) sleep.”

    Calea Zacatechichi · Natural Medicines adverse-effect record, reported in insomnia.

    1 source cited
    1. 23602. Mayagoitia, L., Diaz, J. L., Contreras, C. M. Psychopharmacologic analysis of an alleged oneirogenic plant: Calea zacatechichi. J Ethnopharmacol. 1986;18:229-243. PubMed
  • Vomiting Additional detail

    “Observations in healthy volunteers indicate that Calea zacatechichi is bitter tasting and can cause nausea, vomiting, and retching.”

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

    1 source cited
    1. 23602. Mayagoitia, L., Diaz, J. L., Contreras, C. M. Psychopharmacologic analysis of an alleged oneirogenic plant: Calea zacatechichi. J Ethnopharmacol. 1986;18:229-243. PubMed
  • Nausea Additional detail

    Recorded for Calea Zacatechichi in the same Natural Medicines adverse-effect record shown under Vomiting above.

Everything above comes from the Natural Medicines adverse-effect record for Calea Zacatechichi — 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.

Everything else you take

See Every Supplement That Interacts With Interferon Alfa-2b

This page covers Calea Zacatechichi 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

One more smart check

Taking Calea Zacatechichi as Part of a Dietary Supplement Product? Check It for Interactions

We hold 21 real supplement products containing Calea Zacatechichi, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Calea Zacatechichi. Even though Calea Zacatechichi itself has no known interaction with Interferon Alfa-2b, 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 Calea Zacatechichi 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 Calea Zacatechichi
Steady interest

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

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

#2,433 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 Calea Zacatechichi reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Calea Zacatechichi 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 Calea Zacatechichi

What is Calea Zacatechichi?

  • Promoting vivid or lucid dreams
  • Sleep and relaxation
  • Digestive upset
  • Fever
  • Traditional ritual use

Calea zacatechichi, often called 'dream herb,' is a Mexican plant traditionally used to encourage vivid dreams and to treat digestive complaints and fever. Human research is very limited, so its benefits are not well proven, and its safety has not been carefully studied. It tastes very bitter, can cause nausea, and should be avoided during pregnancy and breastfeeding.

Calea ternifolia · Asteraceae · Leaves and flowering tops (dried) · Dried leaf tea, capsules, tincture/liquid extract, and smoked dried leaf

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

Calea Zacatechichi: dosing

There is no established or standardized dose for Calea zacatechichi. The amount of active compounds can vary a lot from product to product, which makes safe dosing hard to judge.If you choose to use it, follow the directions on the product label and do not exceed them.

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

Read the full Calea Zacatechichi 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 & Calea Zacatechichi

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

0Major
0Moderate
334Minor
2,495No known interaction
Minor

334 interactions

Showing 60 of 334 minor interactions — see all 334 on the Calea Zacatechichi page.

No interaction 2,495 drugs checked — show the list
Evidence & sources

Calea Zacatechichi References

The 2 references that drive our Calea Zacatechichi 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. Mayagoitia, L., Diaz, J. L., Contreras, C. M. Psychopharmacologic analysis of an alleged oneirogenic plant: Calea zacatechichi. J Ethnopharmacol. 1986;18:229-243. PubMed
  2. Roman, Ramos R., Alarcon-Aguilar, F., Lara-Lemus, A., and Flores-Saenz, J. L. Hypoglycemic effect of plants used in Mexico as antidiabetics. Arch.Med.Res 1992;23:59-64.

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 Calea Zacatechichi and Interferon Alfa-2b Together: Common Questions

Is it safe to take Calea Zacatechichi with Interferon Alfa-2b?
We do not list a known interaction between Calea Zacatechichi 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 Calea Zacatechichi 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 Calea Zacatechichi has documented interactions with 2 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 Calea Zacatechichi interact with any other medications?
Yes. Calea Zacatechichi has 334 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 — Calea Zacatechichi 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

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

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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.