Drug & supplement interaction

Hound's Tongue + Phenobarbital, Sodium Nitrate

Phenobarbital, Sodium Nitrate brand name: Soniphen.

Moderate Interaction
Medically reviewed by · Updated October 2026
The bottom line Moderate

Hound's Tongue has a moderate interaction with Phenobarbital, Sodium Nitrate. Theoretically, CYP3A4 inducers can increase the toxicity of the pyrrolizidine alkaloid (PA) constituents of hound's tongue.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Hound's Tongue and Phenobarbital, Sodium Nitrate

Here is the interaction we found between these two, with the evidence behind it.

Moderate

CYTOCHROME P450 3A4 (CYP3A4) INDUCERS

Why this applies to Phenobarbital, Sodium Nitrate

Phenobarbital, Sodium Nitrate falls under CYTOCHROME P450 3A4 (CYP3A4) INDUCERS — the group Hound's Tongue interacts with.

Theoretically, CYP3A4 inducers can increase the toxicity of the pyrrolizidine alkaloid (PA) constituents of hound's tongue.
Hepatotoxic PAs are substrates of cytochrome P450 3A4 (CYP3A4). Drugs that induce CYP3A4 might increase the conversion of PAs to toxic metabolites.
Severity Moderate Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the gist for anyone taking phenobarbital: it's one of the strongest natural "speed-up" signals for a liver enzyme called CYP3A4. Now, Hound's Tongue contains pyrrolizidine alkaloids, which are already known to be hard on the liver. The worry is that phenobarbital revs up the very enzyme that turns those alkaloids into their toxic forms. So combining them could, in theory, make Hound's Tongue more damaging to your liver than usual.

I want to be honest that this concern comes from lab and animal data, not solid human studies, so it's theoretical. That said, Hound's Tongue isn't something I'd recommend swallowing in any case. Please check with your pharmacist or doctor before using it while you're on phenobarbital.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Chojkier M. Hepatic sinusoidal-obstruction syndrome: toxicity of pyrrolizidine alkaloids. J Hepatol 2003;39:437-46. PubMed
  2. Wang YP, Yan J, Fu PP, Chou MW. Human liver microsomal reduction of pyrrolizidine alkaloid N-oxides to form the corresponding carcinogenic parent alkaloid. Toxicol Lett 2005;155:411-20. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Hound's Tongue Also Interacts With Other Medications

Hound's Tongue has 86 moderate known drug interactions in our database — the Phenobarbital, Sodium Nitrate one above is one of them. If you take anything else, check it against the full list below.

Moderate 86 No known interaction 2,744 (incl. Phenobarbital, Sodium Nitrate)
Taking anything else?

Check Another of Your Medications Against Hound's Tongue

Covers the 2,830 medications we’ve checked against Hound's Tongue. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Phenobarbital, Sodium Nitrate

This page covers Hound's Tongue only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Phenobarbital, Sodium Nitrate page lists 141 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Beer (major), Gamma-hydroxybutyrate (ghb) (major) and Kava (major).

By severity: 8 major · 115 moderate · 18 minor.

From our pharmacist’s overview on the Phenobarbital, Sodium Nitrate page

“Phenobarbital with sodium nitrate (Soniphen) is a barbiturate, a heavy sedative used mainly for seizures, and its supplement list calls for real care before you add anything to it. Of the 141 ingredients on file, 78 pile extra sedation onto a drug that already slows breathing and reflexes, and six of the eight major-rated entries sit i…”

Reviewed by 2 · Jul 18, 2026

Open the Phenobarbital, Sodium Nitrate interaction page

One more smart check

Taking Hound's Tongue as Part of a Dietary Supplement Product? Check It for Interactions

We hold 1 real supplement products containing Hound's Tongue, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hound's Tongue. Your product may carry other ingredients that interact with Phenobarbital, Sodium Nitrate too, on top of Hound's Tongue — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Hound's Tongue and Phenobarbital, Sodium Nitrate 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 Hound's Tongue
Top half

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

29 days ago today
Medication Phenobarbital, Sodium Nitrate
Steady interest

#1,443 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.

Supplement

About Hound's Tongue

What is Hound's Tongue?

  • Minor wounds and skin irritation
  • Coughs and sore throat
  • Hemorrhoids
  • Burns and bruises
  • Diarrhea

Hound's Tongue is a traditional folk remedy used mostly on the skin and for coughs, but there is little to no reliable human research showing it works. More importantly, it contains pyrrolizidine alkaloids that can seriously harm the liver, so internal use is generally discouraged. Talk with a pharmacist or doctor before using it in any form.

Read the full Hound's Tongue monograph & all interactions
Keep checking

Other Drugs & Hound's Tongue

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

0Major
86Moderate
0Minor
2,743No known interaction
86 Moderate 2,743 No interaction
Moderate

86 interactions

Showing 60 of 86 moderate interactions — see all 86 on the Hound's Tongue page.

No interaction 2,743 drugs checked — show the list

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

Showing the 60 most looked-up of 2,743 medications checked with no known interaction — see the full Hound's Tongue list.

See the full Hound's Tongue interactions page
See every supplement checked against Phenobarbital, Sodium Nitrate, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Keep exploring
Hound's Tongue monograph › Uses, safety, and every drug interaction in one place Phenobarbital, Sodium Nitrate supplement interactions › Every supplement checked against Phenobarbital, Sodium Nitrate, 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 Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Hound's Tongue and Phenobarbital, Sodium Nitrate Together: Common Questions

Can you take Hound's Tongue with Phenobarbital, Sodium Nitrate?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Hound's Tongue and Phenobarbital, Sodium Nitrate interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Phenobarbital, Sodium Nitrate and Hound's Tongue?

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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.