Sulforaphane + Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine
Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine brand name: Theracaps.
Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine falls into 3 drug categories that Sulforaphane can interact with; the most serious is rated moderate. Theoretically, sulforaphane might alter the levels and clinical effects of CYP1A2 substrates.
Read the full interaction reportSulforaphane and Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine
These two interact in 3 distinct ways. Each one is explained separately below.
Why Are There 3 Interactions?
Sulforaphane interacts with whole categories of medication. Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine falls into 3 of those categories, so it can interact with Sulforaphane in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).
CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES
1 of 3Why this applies to Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine
Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Sulforaphane interacts with.
Animal and in vitro research shows that sulforaphane inhibits CYP1A2 enzyme activity. However, its precursor glucoraphanin also appears to increase the expression of the CYP1A2 enzyme, which could lead to increased metabolism of CYP1A2 substrates. These effects have not been reported in humans.
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.
Your Theracaps combo (acetaminophen, dextromethorphan, phenylpropanolamine, and pyrilamine) is a cold-and-cough product. The piece that touches this interaction is the liver enzyme called CYP1A2, which helps process some of these ingredients. In lab and animal studies, sulforaphane has shown a confusing, two-way effect: it can block this enzyme, but its broccoli-derived precursor can also speed it up. In plain terms, no one really knows which direction wins in real people.
The important part: this has never been shown in humans, and it comes only from test-tube and animal work. Broccoli on your plate is not a concern. A concentrated sulforaphane supplement is worth mentioning to your pharmacist, but I would not lose sleep over it.
- Barcelo S, Mace K, Pfeifer AM, Chipman JK. Production of DNA strand breaks by N-nitrosodimethylamine and 2-amino-3-methylimidazo[4,5-f]quinoline in THLE cells expressing human CYP isoenzymes and inhibition by sulforaphane. Mutat Res 1998;402:111-20. PubMed
- Fimognari C, Lenzi M, Hrelia P. Interaction of the isothiocyanate sulforaphane with drug disposition and metabolism: pharmacological and toxicological implications. Curr Drug Metab. 2008;9(7):668-78. PubMed
- Chinnappan SM, George A, Evans M, Anthony J. Efficacy of Labisia pumila and Eurycoma longifolia standardised extracts on hot flushes, quality of life, hormone and lipid profile of peri-menopausal and menopausal women: a randomised, placebo-controlled stud
CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES
2 of 3Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.
Animal and in vitro research shows that sulforaphane inhibits CYP3A4 enzyme activity and downregulates its expression. This interaction has not been reported in humans.
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.
This combo product (Theracaps) mixes a few cold-and-cough medicines, and the one that leans on the CYP3A4 enzyme is the dextromethorphan (the cough suppressant). Sulforaphane, the compound concentrated from broccoli, has been shown in lab dishes and animals to slow that enzyme down. In theory, that could let dextromethorphan build up a bit, which might mean more drowsiness, dizziness, or a foggy, lightheaded feeling.
Here's the honest part: this has only been seen in test-tube and animal studies, never reported in real people, so it's mostly theoretical. Eating broccoli or other cruciferous veggies almost certainly won't matter. If you take a concentrated sulforaphane supplement and use this product often, just give your pharmacist a quick heads-up so they can check it for you.
- Fimognari C, Lenzi M, Hrelia P. Interaction of the isothiocyanate sulforaphane with drug disposition and metabolism: pharmacological and toxicological implications. Curr Drug Metab. 2008;9(7):668-78. PubMed
- Mahéo K, Morel F, Langouët S, et al. Inhibition of cytochromes P-450 and induction of glutathione S-transferases by sulforaphane in primary human and rat hepatocytes. Cancer Res. 1997;57(17):3649-52.
- Yoxall V, Kentish P, Coldham N, Kuhnert N, Sauer MJ, Ioannides C. Modulation of hepatic cytochromes P450 and phase II enzymes by dietary doses of sulforaphane in rats: Implications for its chemopreventive activity. Int J Cancer. 2005;117(3):356-62. PubMed
CYTOCHROME P450 2E1 (CYP2E1) SUBSTRATES
3 of 3Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine also falls under CYTOCHROME P450 2E1 (CYP2E1) SUBSTRATES.
In vitro evidence shows that sulforaphane inhibits CYP2E1 enzymes. This interaction has not been reported in humans.
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.
This combo cold product (Theracaps) has a few ingredients, but the piece that matters here is the acetaminophen. Acetaminophen is partly handled by a liver enzyme called CYP2E1. In test tube studies, sulforaphane has been shown to slow this enzyme down a bit. The interesting thing is that CYP2E1 is the pathway that turns a small amount of acetaminophen into a harmful byproduct, so in theory, slowing it could actually mean less of that toxic byproduct, not more.
Here's the honest part: this has only been seen in lab dishes, never confirmed in real people, so I wouldn't lose sleep over it. Broccoli on your plate is no concern at all. If you take a concentrated sulforaphane capsule along with regular acetaminophen, just give your pharmacist a heads-up and stick to the labeled acetaminophen dose.
- Fimognari C, Lenzi M, Hrelia P. Interaction of the isothiocyanate sulforaphane with drug disposition and metabolism: pharmacological and toxicological implications. Curr Drug Metab. 2008;9(7):668-78. PubMed
What These Ratings Mean
Every interaction above is graded three ways — here’s the key to each label.
Clinically significant. Avoid the combination, or use only under close professional supervision.
Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.
Generally not serious. Be aware of it and mention it to your pharmacist.
- 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.
- 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.
Sulforaphane Also Interacts With Other Medications
Sulforaphane has 721 moderate known drug interactions in our database — the Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine one above is among them. If you take anything else, check it against the full list below.
Check Another of Your Medications Against Sulforaphane
We haven’t checked that one against Sulforaphane yet — ask our pharmacists directly.
Covers the 2,830 medications we’ve checked against Sulforaphane. Pick one to open its full report.
See Every Supplement That Interacts With Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine
This page covers Sulforaphane only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine page lists 282 supplements it has a documented interaction with, worst first, each one explained.
The most serious there right now: Activated Charcoal (major), Asarabacca (major), Beer (major), Ephedra (major) and Grapefruit (major).
By severity: 14 major · 223 moderate · 45 minor.
From our pharmacist’s overview on the Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine page
“Of everything on this page, ephedra worries me most for anyone using Theracaps (acetaminophen, dextromethorphan, phenylpropanolamine, and pyrilamine), because the decongestant in this cold formula is itself a stimulant. Adding ephedra or any of the 44 stimulant entries can push blood pressure and heart rate to unsafe levels.”
Reviewed by 2 · Jul 18, 2026
Open the Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine interaction page
Taking Sulforaphane as Part of a Dietary Supplement Product? Check It for Interactions
We hold 167 real supplement products containing Sulforaphane, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Sulforaphane. Your product may carry other ingredients that interact with Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine too, on top of Sulforaphane — and those would not show on this page. Find your product and we’ll check every ingredient on its label:
Where Sulforaphane and Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine 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.
#522 of 1,452 supplements looked up here in the last 7 days
#160 of 2,830 medications looked up here in the last 7 days
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.
About Sulforaphane
What is Sulforaphane?
- Antioxidant support
- General cellular health
- Detoxification support
- Inflammation
- Skin and aging concerns
Sulforaphane is a natural compound found in broccoli and other cruciferous vegetables that has shown promising antioxidant and anti-inflammatory effects in lab studies, but strong human evidence for most specific health claims is still limited. It is generally well tolerated as part of a vegetable-rich diet, but if you take a concentrated supplement, talk to your pharmacist or doctor first.
Other Drugs & Sulforaphane
Browse every other medication we’ve checked against Sulforaphane — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
721 interactions
- Diltiazem ›
- Theophylline ›
- Nifedipine ›
- Hydrocortisone ›
- Naproxen ›
- Erythromycin ›
- Estradiol ›
- Propranolol ›
- Lidocaine ›
- Norethindrone ›
- Testosterone ›
- Verapamil ›
- Levonorgestrel ›
- Prednisone ›
- Quinidine ›
- Cyclosporine ›
- Dexamethasone ›
- Triazolam ›
- Zopiclone ›
- Colchicine ›
- Fentanyl ›
- Oxybutynin ›
- Prednisolone ›
- Tacrolimus ›
- Temazepam ›
- Budesonide ›
- Carbamazepine ›
- Clindamycin ›
- Dextromethorphan ›
- Doxorubicin ›
- Fluticasone ›
- Miconazole ›
- Acetaminophen ›
- Buprenorphine ›
- Conjugated Estrogens ›
- Diazepam ›
- Everolimus ›
- Ivabradine ›
- Lofepramine ›
- Medroxyprogesterone ›
- Medroxyprogesterone Acetate ›
- Nortriptyline ›
- Rifampin ›
- Testosterone Undecanoate ›
- Aripiprazole ›
- Bendamustine ›
- Caffeine (otc Drug) ›
- Ciclesonide ›
- Clonazepam ›
- Cyclobenzaprine ›
- Dapsone ›
- Desipramine ›
- Erythromycin Ethylsuccinate ›
- Erythromycin Stearate ›
- Etoposide ›
- Fluticasone Propionate ›
- Hydroxyzine ›
- Itraconazole ›
- Midazolam ›
- Modafinil ›
Showing 60 of 721 moderate interactions — see all 721 on the Sulforaphane page.
No interaction 2,108 drugs checked — show the list
We also checked Sulforaphane against these medications and found no known interaction in our sources. Open any page to confirm.
- Levothyroxine ›
- Methylphenidate ›
- Ivermectin ›
- Aspirin ›
- Rosuvastatin ›
- Metoprolol ›
- Escitalopram ›
- Methamphetamine ›
- Tirzepatide ›
- Ibuprofen ›
- Docusate ›
- Sumatriptan ›
- Valacyclovir ›
- Hydroxyurea ›
- Isotretinoin ›
- Semaglutide ›
- Metformin ›
- Lisdexamfetamine ›
- Methotrexate ›
- Amphetamine ›
- Lisinopril ›
- Amoxicillin ›
- Bupropion ›
- Fluoxetine ›
- Doxycycline ›
- Pregabalin ›
- Azithromycin ›
- Levothyroxine, Liothyronine ›
- Lamotrigine ›
- Acyclovir ›
- Gabapentin ›
- Dextroamphetamine ›
- Duloxetine ›
- Methylene Blue ›
- Ciprofloxacin ›
- Bisoprolol ›
- Candesartan Cilexetil ›
- Amoxicillin, Clavulanate Potassium ›
- Acetylsalicylic Acid ›
- Cephalexin ›
- Cyclopentolate ›
- Ezetimibe ›
- Carbidopa, Levodopa ›
- Acetaminophen, Dextromethorphan, Doxylamine ›
- Roxithromycin ›
- Levetiracetam ›
- Mannitol ›
- Insulin Degludec, Liraglutide ›
- Thyroid Hormone ›
- Levodopa ›
- Spironolactone ›
- Valsartan ›
- Mitomycin ›
- Canagliflozin, Metformin ›
- Venlafaxine ›
- Alginic Acid, Aluminum Hydroxide ›
- Aspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium Hydroxide ›
- Dexmethylphenidate ›
- Levothyroxine Sodium ›
- Atenolol ›
Showing the 60 most looked-up of 2,108 medications checked with no known interaction — see the full Sulforaphane list.
Sources & How We Checked
Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference for vitamins, herbs and supplements — the basis for our interaction data.
- MedlinePlus, U.S. National Library of Medicine — NIH consumer drug information, used for the medication overviews.
- NIH Dietary Supplement Label Database (DSLD) — Official supplement product labels.
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
Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine Is Linked to Lower Levels of One Nutrient
Natural Medicines records Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine as a medicine that can lower these. This is not an interaction with Sulforaphane — it is a separate effect of the medicine, and it is a reason some people are advised to supplement rather than to avoid one:
Depletion records come from the licensed Natural Medicines database. Do not start a supplement on the strength of this page — ask your pharmacist or doctor whether it applies to you.
Taking Sulforaphane and Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine Together: Common Questions
Can you take Sulforaphane with Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine?
Why are there 3 interactions listed for Sulforaphane and Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine?
How serious is the Sulforaphane and Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine interaction?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Still Have a Question About Acetaminophen, Dextromethorphan, Phenylpropanolamine, Pyrilamine and Sulforaphane?
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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.