Medication interaction hub

What Supplements Interact with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Chlorpheniramine, Phenylephrine, Phenyltoloxamine brand names: Com Time, Q Hist LA, Comhist LA, Linhist LA, Comhist. Every interaction below applies to the brands too.

229 Interactions 10 Major 175 Moderate 44 Minor
Curated & coded by · Clinical Pharmacist · Updated September 23, 2026

Drug–supplement interaction data sourced from Natural Medicines Pro, the licensed clinical database from TRC Healthcare / Therapeutic Research, with additional analysis by the HelloPharmacist Pharmacist Team. Our sources · Editorial policy

What is this page for?

One answer, for one medication: what supplements and herbal products interact with Chlorpheniramine, Phenylephrine, Phenyltoloxamine? Every vitamin, herb, and supplement ingredient we’ve checked against it is on this page, ranked by severity, each linking to the full report for that exact pair.

This page covers supplement interactions only — to check Chlorpheniramine, Phenylephrine, Phenyltoloxamine against your other medications, use the drug–drug interaction checker. Educational information from our licensed clinical databases, not medical advice. Our editorial policy

HelloPharmacist Bottom Line
Our Pharmacist Explains
What is this? The interaction data in the HelloPharmacist supplement database is licensed from Natural Medicines Pro by TRC Healthcare (Therapeutic Research). HelloPharmacist pharmacists often add our own analysis and context on top of that licensed data — such as this Bottom Line summary and the notes on individual interaction pages — and any such commentary is noted as ours.

If you take Comhist (chlorpheniramine, phenylephrine, and phenyltoloxamine, a cold and allergy combination), treat its supplement list with real care. Ten of the 229 ingredients on file carry a major rating, and the biggest patterns are worth knowing. Grapefruit and St. John's wort can raise or lower how much of the medicine stays in your blood, and 44 stimulant ingredients can add to phenylephrine's push on your heart and blood pressure.

The antihistamines in this combo already dry you out and slow you down, and 30 herbs pile those same effects on top: more drowsiness, dry mouth, and constipation. Others add sun sensitivity or serotonin effects, and activated charcoal can soak up the dose before it works. The rest sit mostly at moderate (175, with 44 minor), but read the ten majors first and match them against what you actually take.

— , Clinical Pharmacist · July 18, 2026

Major 10 Moderate 175 Minor 44 No known interaction 1,223

This box checks one ingredient at a time (like turmeric or magnesium). Taking a supplement product with a whole label of ingredients? Search the product instead — we check every ingredient on it ↓

Top Ingredient Interactions

Chlorpheniramine, Phenylephrine, Phenyltoloxamine: Top Interactions at a Glance

The most significant Chlorpheniramine, Phenylephrine, Phenyltoloxamine supplement & herbal interactions, colored by severity. Tap any ingredient to open the full report for that pair.

Showing the 12 highest-ranked of 229 interacting ingredients — plus 1,223 more checked with no known interaction. See the complete ranked list.

Start here

The Major Interactions to Know About

The most clinically significant Chlorpheniramine, Phenylephrine, Phenyltoloxamine + supplement combinations in our database, best-documented first. Open any card for the full report.

Major Likelihood Likely Grapefruit + Chlorpheniramine, Phenylephrine, Phenyltoloxaminei

Grapefruit juice can increase levels of drugs metabolized by CYP3A4.

Read the full interaction Major Likelihood Probable Activated Charcoal + Chlorpheniramine, Phenylephrine, Phenyltoloxaminei

Activated charcoal reduces systemic exposure to many drugs, including those that undergo enterohepatic recirculation, regardless of the route of administration.

Read the full interaction Major Likelihood Probable Ephedra + Chlorpheniramine, Phenylephrine, Phenyltoloxaminei

Theoretically, concomitant use might increase the risk for serious adverse effects.

Read the full interaction Major Likelihood Probable Henbane + Chlorpheniramine, Phenylephrine, Phenyltoloxaminei

Concomitant use of henbane can have additive anticholinergic effects and adverse effects with amantadine, antihistamines, atropine, belladonna alkaloids, hyoscy...

Read the full interaction Major Likelihood Probable Lithium + Chlorpheniramine, Phenylephrine, Phenyltoloxaminei

Theoretically, taking lithium supplements with serotonergic drugs might both mask and increase the risk of serotonin syndrome.

Read the full interaction Major Likelihood Probable Peyote + Chlorpheniramine, Phenylephrine, Phenyltoloxaminei

Concomitant use of peyote with stimulant drugs may increase the risk of adverse CNS effects.

Read the full interaction
The complete list

Every Supplement Checked Against Chlorpheniramine, Phenylephrine, Phenyltoloxamine

All 1,452 ingredients in our database, ranked by severity — 229 with a Chlorpheniramine, Phenylephrine, Phenyltoloxamine interaction on file and 1,223 with none found. Filter by severity or search any ingredient; hover the for what each ingredient is.

Looking for an interaction with a specific supplement product? Search products instead ↓

Straight answers

Can You Take It With Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

One-line answers, one card per combination — scroll through today’s 20 and tap any card for the full report. A different set rotates in daily until every combination has had its turn.

Can you take Henbane with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Concomitant use of henbane can have additive anticholinergic effects and adverse effects with amantadine, antihistamines, atropine, belladon...

Full Henbane + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Goldthread with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. There's very preliminary evidence that berberine, a constituent of goldthread, might inhibit cytochrome P450 3A4 (CYP3A4) enzyme.

Full Goldthread + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Lithium with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Theoretically, taking lithium supplements with serotonergic drugs might both mask and increase the risk of serotonin syndrome.

Full Lithium + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Peyote with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Concomitant use of peyote with stimulant drugs may increase the risk of adverse CNS effects.

Full Peyote + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Rauvolfia Vomitoria with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Theoretically, concomitant use might cause additive effects.

Full Rauvolfia Vomitoria + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Scopolia with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. The alkaloid constituents of scopolia, including hyoscyamine, scopolamine, and atropine, could potentiate the effects and adverse effects of...

Full Scopolia + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Sida Cordifolia with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Theoretically, Sida cordifolia might increase the risk of adverse cardiovascular effects when taken with stimulant drugs.

Full Sida Cordifolia + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take St. John's Wort with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. St.

Full St. John's Wort + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Belladonna with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Belladonna may increase the risk of adverse effects when used concomitantly with anticholinergic drugs.

Full Belladonna + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Bergamot with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, topical bergamot essential oil might increase the risk of side effects when used along with photosensitizing drugs.

Full Bergamot + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Betel Nut with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. In vitro and animal research suggests that betel nut extract can inhibit acetylcholinesterase activity.

Full Betel Nut + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Black Tea with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use might increase stimulant adverse effects.

Full Black Tea + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Caffeine with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use might increase stimulant adverse effects.

Full Caffeine + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Cannabidiol (cbd) with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Cannabidiol may increase levels of drugs that are metabolized by CYP3A4.

Full Cannabidiol (cbd) + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Chenopodium Oil with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use of chenopodium oil with other photosensitizing drugs can increase the risk of adverse effects.

Full Chenopodium Oil + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Chlorophyll with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use of chlorophyll with photosensitizing drugs may have additive effects.

Full Chlorophyll + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Chlorophyllin with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use of chlorophyllin with photosensitizing drugs may have additive effects.

Full Chlorophyllin + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Cocoa with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use might increase stimulant adverse effects.

Full Cocoa + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Coffee with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use might increase stimulant adverse effects.

Full Coffee + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer

Can you take Coffee Charcoal with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Coffee charcoal can reduce the absorption of orally administered drugs and should be separated from oral drug administration by at least two...

Full Coffee Charcoal + Chlorpheniramine, Phenylephrine, Phenyltoloxamine answer
Read the list like a pharmacist

What Severity, Likelihood & Evidence Mean

Severity — How Serious It Can Be

  • Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
  • Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
  • Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
  • No known interaction. Checked against our sources with nothing documented — not the same as proven safety.

Likelihood — How Well It’s Documented

  • Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
  • Probable. Interaction 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.
  • Possible. 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
  • Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.

Where This Data Comes From

  • Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
  • Each entry links to a full report with the clinical detail, likelihood, evidence level, and citations for that exact combination.
  • Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

How Does Our Interaction Checker Work?

Behind every verdict on this page is a category system. Our source database doesn’t document supplement interactions drug-by-drug — it documents them against groups of medications that behave the same way (for example, “drugs processed by the CYP3A4 liver enzyme” or “blood-thinning medications”).

So the check works in three steps: (1) Chlorpheniramine, Phenylephrine, Phenyltoloxamine is classified into the pharmacology categories it belongs to, (2) every supplement interaction documented against any of those categories is inherited by Chlorpheniramine, Phenylephrine, Phenyltoloxamine, and (3) each ingredient keeps its own severity, likelihood, and evidence grades from the underlying record. That’s why one supplement can carry several records for one drug — it may interact through more than one category.

Chlorpheniramine, Phenylephrine, Phenyltoloxamine sits in 10 interaction categories. Open any one to see what the group means:

Cytochrome P450 3A4 (Cyp3A4) Substrates 121 ingredients

A drug-metabolism group: these medications are processed by the named liver enzyme (a cytochrome P450). Supplements that speed this enzyme up or slow it down can lower or raise the medication's levels in your body.

121 of the supplement ingredients on this page reach Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Stimulant Drugs 44 ingredients

A pharmacology grouping from our source database: medications in this group share a property that certain supplements are known to interact with, so an interaction documented for the group applies to every drug in it.

44 of the supplement ingredients on this page reach Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Anticholinergic Drugs 30 ingredients

A pharmacology grouping from our source database: medications in this group share a property that certain supplements are known to interact with, so an interaction documented for the group applies to every drug in it.

30 of the supplement ingredients on this page reach Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Photosensitizing Drugs 20 ingredients

Medications that make skin more sun-sensitive. Supplements with the same property can compound it.

20 of the supplement ingredients on this page reach Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Serotonergic Drugs 20 ingredients

Medications that raise serotonin activity. Combining them with serotonin-active supplements can, in rare cases, push serotonin too high.

20 of the supplement ingredients on this page reach Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Oral Drugs 17 ingredients

A pharmacology grouping from our source database: medications in this group share a property that certain supplements are known to interact with, so an interaction documented for the group applies to every drug in it.

17 of the supplement ingredients on this page reach Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Seizure Threshold Lowering Drugs 6 ingredients

A pharmacology grouping from our source database: medications in this group share a property that certain supplements are known to interact with, so an interaction documented for the group applies to every drug in it.

6 of the supplement ingredients on this page reach Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Cytochrome P450 2D6 (Cyp2D6) Inhibitors 3 ingredients

A drug-metabolism group: these medications are processed by the named liver enzyme (a cytochrome P450). Supplements that speed this enzyme up or slow it down can lower or raise the medication's levels in your body.

3 of the supplement ingredients on this page reach Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Alpha-Adrenergic Agonists 1 ingredient

A pharmacology grouping from our source database: medications in this group share a property that certain supplements are known to interact with, so an interaction documented for the group applies to every drug in it.

1 of the supplement ingredient on this page reaches Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Serotonergic Drugs 1 ingredient

Medications that raise serotonin activity. Combining them with serotonin-active supplements can, in rare cases, push serotonin too high.

1 of the supplement ingredient on this page reaches Chlorpheniramine, Phenylephrine, Phenyltoloxamine through this category.

Check a real product

Take a Supplement Product? Check the Whole Bottle Against Chlorpheniramine, Phenylephrine, Phenyltoloxamine

Most supplements are combination products — and the interaction may come from an ingredient you didn’t buy it for. Search any product below (or scan its label) and we’ll check every ingredient on it against Chlorpheniramine, Phenylephrine, Phenyltoloxamine.

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Pharmacist Counseling Corner

Chlorpheniramine, Phenylephrine, Phenyltoloxamine & Supplements: Common Questions

What supplements interact with Chlorpheniramine, Phenylephrine, Phenyltoloxamine?
In our interaction database, 229 supplement and herbal ingredients have an interaction with Chlorpheniramine, Phenylephrine, Phenyltoloxamine on file — 10 rated major, 175 moderate, and 44 minor. That number sounds scarier than it is: severity matters far more than the count, which is why the list on this page is ranked instead of alphabetical. Start at the top. The highest-ranked right now: Grapefruit, Activated Charcoal, Ephedra.
Which Chlorpheniramine, Phenylephrine, Phenyltoloxamine supplement interactions are the most serious?
Focus on the major group: Grapefruit, Activated Charcoal, Ephedra, Henbane and Lithium, among others. A major rating means the combination can be clinically significant, not that harm is guaranteed — but it's exactly the kind of thing to run past your pharmacist before your next dose, not after. Jump to the ranked list.
Can I take vitamins or supplements while on Chlorpheniramine, Phenylephrine, Phenyltoloxamine?
That depends entirely on which supplement. The honest answer for Chlorpheniramine, Phenylephrine, Phenyltoloxamine is in the ranked list above — and if what you take is a combination product with a dozen ingredients, don't check them one by one: photograph the label with our scanner and we'll check the whole thing at once. Try the label scanner or the interaction checker.
Do brands like Com Time have the same supplement interactions as Chlorpheniramine, Phenylephrine, Phenyltoloxamine?
Yes — Com Time, Q Hist LA, Comhist LA, Linhist LA, Comhist all contain Chlorpheniramine, Phenylephrine, Phenyltoloxamine, so everything on this page applies to them equally. Interactions belong to the active drug, never to the brand on the box; the same is true of generics.
Where do these interaction ratings come from?
Every rating comes from the Natural Medicines database — the same evidence-graded reference pharmacists and hospitals use — and each interaction carries three separate grades: severity (how bad it can be), likelihood (how well it's documented in studies and case reports), and an evidence level. Our pharmacists review the content; we never let an AI decide an interaction. See how to read the ratings and our editorial policy.
What about Chlorpheniramine, Phenylephrine, Phenyltoloxamine and my other medications?
This page covers Chlorpheniramine, Phenylephrine, Phenyltoloxamine against supplements and herbal ingredients. Checking Chlorpheniramine, Phenylephrine, Phenyltoloxamine against your other prescription or OTC medications is a different tool — our drug interaction checker covers that side. Head to the drug–drug interaction checker.

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

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Sourcing

Where This Data Comes From — and Why You Can Trust It

🧪 Licensed clinical database

Every interaction verdict on this page comes from Natural Medicines Pro (TRC Healthcare / Therapeutic Research) — the same evidence-graded reference used by pharmacists and hospitals. We license this data directly; we do not scrape it, and no AI invents an interaction.

🧑‍⚕️ Pharmacist review

This page is curated and coded by , Clinical Pharmacist, with additional analysis by the HelloPharmacist Pharmacist Team. Editorial commentary is ours; the licensed interaction records are shown as sourced.

🔄 Kept current

Our interaction database refreshes on a weekly cycle, and this page re-checks the live database every time it’s rebuilt — what you see reflects the database as of September 23, 2026.

🔍 Full transparency

How every dataset on this site is sourced, licensed, and updated is documented publicly: our data sources · editorial policy · how we use AI.

Educational information, not medical advice. An interaction being on file does not mean it will happen to you — and absence of one is not proof of safety. Never start or stop a medication or supplement without talking to your pharmacist or doctor.