Drug & supplement interaction

Oscillococcinum + Dextromethorphan

Dextromethorphan brand names: Hold, Benylin Adult, Benylin Pediatric, Theraflu Thin Strips Long Acting Cough, Neo Citran Thin Strips Cough.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Oscillococcinum and Dextromethorphan 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

Oscillococcinum and Dextromethorphan

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 Dextromethorphan and Oscillococcinum 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 Oscillococcinum at all — not against Dextromethorphan, 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.

Oscillococcinum safety at a glance

Oscillococcinum overall Use caution Generally well tolerated, but evidence of benefit is lacking and it should not replace proven flu care.
Pregnancy Use caution Safety has not been well studied in pregnancy, so check with your doctor first.
Breastfeeding Use caution Little data exists during breastfeeding, so use only with medical guidance.

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

Still wondering about combining Dextromethorphan and Oscillococcinum? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
What to actually watch for

What Oscillococcinum Itself Has Been Linked To

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

  • A severe allergic reaction Worth acting on Additional detail

    “Orally, oscillococcinum has been associated with angioedema. Three cases of angioedema have been reported. In one case, a 34-year-old male developed mild stridor and a markedly swollen tongue after taking oscillococcinum for flu-like symptoms. The patient was treated with intramuscular epinephrine and intravenous diphenhydramine and methylprednisolone.”

    Oscillococcinum · Natural Medicines adverse-effect record, reported in influenza.

    1 source cited
    1. 92284. Azmi Y, Rao M, Verma I, Agrawal A. Oscillococcinum leading to angioedema, a rare adverse event. BMJ Case Rep. 2015 Jun 2;2015. PubMed
  • Headache Additional detail

    “Orally, oscillococcinum has been associated with one report of headache in one clinical study.”

    Oscillococcinum · Natural Medicines adverse-effect record, reported in cluster headache.

    1 source cited
    1. 19063. Papp R, Schuback G, Beck E, et al. Oscillococcinum in patients with influenza-like syndromes: a placebo-controlled double-blind evaluation. British Homoeopathic Journal 1998;87:69-76.

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

From our Q&A

Questions About Oscillococcinum or Dextromethorphan

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Oscillococcinum or Dextromethorphan, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Dextromethorphan

This page covers Oscillococcinum only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dextromethorphan page lists 171 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), Lithium (major), St. John's Wort (major) and 1,3-dmaa (moderate).

By severity: 4 major · 125 moderate · 42 minor.

From our pharmacist’s overview on the Dextromethorphan page

“A glass of grapefruit juice can push dextromethorphan (Benylin, Hold, and other cough medicines) to higher levels than intended, one of four major-rated entries among the 171 supplements and herbs on file, and the list as a whole warrants real care. Most interactions trace back to the liver enzymes (CYP3A4 and CYP2D6) that clear dextro…”

Reviewed by 2 · Jul 18, 2026

Open the Dextromethorphan interaction page

How much people look this up

Where Oscillococcinum and Dextromethorphan 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 Oscillococcinum
Steady interest

#1,202 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Dextromethorphan
Top 25%

#381 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 Oscillococcinum reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Oscillococcinum and Dextromethorphan 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 Oscillococcinum

What is Oscillococcinum?

  • Flu-like symptoms
  • Common cold symptoms
  • Body aches and chills
  • Fatigue during illness
  • Fever associated with the flu

Oscillococcinum is a homeopathic product made from extremely diluted duck liver and heart, marketed to ease flu-like symptoms. High-quality research has not shown it works better than a placebo, but it is generally well tolerated. If you choose to try it, see it as a low-risk option rather than a proven treatment, and don't use it to replace a flu vaccine or needed medical care.

Anas barbariae hepatis et cordis extractum · Highly diluted extract of duck liver and heart (Muscovy duck) · Oral pellets/granules that dissolve under the tongue

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

Oscillococcinum: dosing

There is no scientifically established effective dose for Oscillococcinum, since it has not been shown to work. If you choose to use it, follow the directions on the product label exactly.The pellets are typically dissolved under the tongue rather than swallowed with water, and packages often suggest starting at the first sign of symptoms.

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

Read the full Oscillococcinum monograph & all interactions
Medication

About Dextromethorphan

What Is Dextromethorphan Used For?

Brand names: Hold, Benylin Adult, Benylin Pediatric, Theraflu Thin Strips Long Acting Cough, Neo Citran Thin Strips Cough

Dextromethorphan temporarily relieves cough due to minor throat and bronchial irritation, such as the kind that comes with the common cold or breathing in irritants. It also helps reduce the urge to cough so you — or your child — can get to sleep.

Some products, including CVS Long Acting Cough and Premier Value Tussin Cough oral liquids, are also indicated to help loosen phlegm (mucus) and thin bronchial secretions to help drain the airways.

See full Dextromethorphan drug information
Keep checking

Other Drugs & Oscillococcinum

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

0Major
0Moderate
0Minor
2,829No known interaction
No interaction 2,829 drugs checked — show the list
Evidence & sources

Oscillococcinum References

The 2 references that drive our Oscillococcinum 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. Papp R, Schuback G, Beck E, et al. Oscillococcinum in patients with influenza-like syndromes: a placebo-controlled double-blind evaluation. British Homoeopathic Journal 1998;87:69-76.
  2. Azmi Y, Rao M, Verma I, Agrawal A. Oscillococcinum leading to angioedema, a rare adverse event. BMJ Case Rep. 2015 Jun 2;2015. 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 Oscillococcinum and Dextromethorphan Together: Common Questions

Is it safe to take Oscillococcinum with Dextromethorphan?
We do not list a known interaction between Oscillococcinum and Dextromethorphan. 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.
Does Dextromethorphan interact with any supplements?
Yes. Dextromethorphan has documented interactions with 171 supplements in our database — Oscillococcinum is not one of them. The Dextromethorphan 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 Dextromethorphan and Oscillococcinum?

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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.