Lentinan + Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine
Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine brand name: Conar-A.
Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine falls into 3 drug categories that Lentinan can interact with; the most serious is rated moderate. Laboratory evidence suggests that lentinan might increase the activity of cytochrome P450 1A2 (CYP1A2).
Read the full interaction reportLentinan and Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine
These two interact in 3 distinct ways. Each one is explained separately below.
Why Are There 3 Interactions?
Lentinan interacts with whole categories of medication. Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine falls into 3 of those categories, so it can interact with Lentinan 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, Guaifenesin, Phenylephrine
Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Lentinan interacts with.
Some drugs metabolized by CYP1A2 include amitriptyline (Elavil), haloperidol (Haldol), ondansetron (Zofran), propranolol (Inderal), theophylline (Theo-Dur, others), verapamil (Calan, Isoptin, others), and others.
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.
Here's the honest version: this multi-symptom cold and cough combo (acetaminophen, dextromethorphan, guaifenesin, and phenylephrine) isn't really driven by CYP1A2. The lab note about lentinan possibly speeding up that enzyme is based only on test-tube and animal data, and it has never been shown in people. So for this particular product, I'd put this interaction very low on your worry list.
If anything, the bigger point is that lentinan oral supplements vary a lot in quality and aren't well studied. I wouldn't expect it to change how well your cold medicine works or cause new side effects. Still, since you're combining things, it's worth a quick chat with your pharmacist, especially if you take it regularly or have other health conditions.
- Lin Y, Wei Y, Hu X, et al. Evaluation of lentinan effects on cytochrome P450 activity in rats by a cocktail method. Iran J Basic Med Sci. 2019;22(3):296-301.
CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES
2 of 3Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine also falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES.
Some drugs metabolized by CYP2D6 include tricyclic antidepressants such as imipramine (Tofranil) and amitriptyline (Elavil); antipsychotics such as haloperidol (Haldol), risperidone (Risperdal), and chlorpromazine (Thorazine); beta-blockers such as propranolol (Inderal), metoprolol (Lopressor, Toprol XL), and carvedilol (Coreg); tamoxifen (Nolvadex); and others.
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.
In this combo cold-and-cough product, the ingredient that matters here is dextromethorphan (the cough suppressant). Your body relies on an enzyme called CYP2D6 to break it down. Lab studies hint that lentinan might speed up that enzyme, which could clear dextromethorphan a little faster and make it slightly less effective at quieting a cough. The other ingredients (acetaminophen, guaifenesin, phenylephrine) aren't really driven by this pathway, so they're not the concern.
Honestly, this is only suggested by test-tube and animal research, not seen in real people, so I wouldn't lose sleep over it. If you take both and notice your cough medicine just isn't working as well, mention it to your pharmacist or doctor before changing anything.
- Lin Y, Wei Y, Hu X, et al. Evaluation of lentinan effects on cytochrome P450 activity in rats by a cocktail method. Iran J Basic Med Sci. 2019;22(3):296-301.
CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES
3 of 3Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.
Some drugs metabolized by CYP3A4 include lovastatin (Mevacor), ketoconazole (Nizoral), itraconazole (Sporanox), fexofenadine (Allegra), triazolam (Halcion), and numerous others.
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 cold and cough combo (Conar-A) has a few ingredients, and the one most likely tied up with this interaction is dextromethorphan, the cough suppressant, which is partly handled by the CYP3A4 enzyme. Lab research hints that lentinan may speed up CYP3A4. In theory, that could clear dextromethorphan a bit faster and make it slightly less effective at quieting your cough.
Honestly, I would not lose sleep over this one. The evidence is only from test tube and animal studies, it has never been reported in real people, and these are short-term, over-the-counter symptom relievers. The acetaminophen, guaifenesin, and phenylephrine pieces aren't meaningfully affected here. If you use lentinan regularly, just mention it to your pharmacist so they can keep an eye on things.
- Lin Y, Wei Y, Hu X, et al. Evaluation of lentinan effects on cytochrome P450 activity in rats by a cocktail method. Iran J Basic Med Sci. 2019;22(3):296-301.
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.
Lentinan Also Interacts With Other Medications
Lentinan has 813 moderate known drug interactions in our database — the Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine one above is among them. If you take anything else, check it against the full list below.
Check Another of Your Medications Against Lentinan
We haven’t checked that one against Lentinan yet — ask our pharmacists directly.
Covers the 2,830 medications we’ve checked against Lentinan. Pick one to open its full report.
See Every Supplement That Interacts With Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine
This page covers Lentinan only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine page lists 261 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: 12 major · 206 moderate · 43 minor.
From our pharmacist’s overview on the Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine page
“Picture the week someone takes Conar-A (acetaminophen, dextromethorphan, guaifenesin, phenylephrine): a miserable cold, coffee to push through, maybe wine at night or an herbal remedy on top. Those habits are exactly where this list turns serious.”
Reviewed by 2 · Jul 18, 2026
Open the Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine interaction page
Taking Lentinan as Part of a Dietary Supplement Product? Check It for Interactions
We hold 1 real supplement products containing Lentinan, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Lentinan. Your product may carry other ingredients that interact with Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine too, on top of Lentinan — and those would not show on this page. Find your product and we’ll check every ingredient on its label:
Where Lentinan and Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine 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.
#747 of 1,452 supplements looked up here in the last 7 days
#543 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 Lentinan
What is Lentinan?
- Immune support
- Used alongside cancer treatment
- Anti-inflammatory
- General wellness/tonic
- Antimicrobial support
Lentinan is a beta-glucan polysaccharide from shiitake mushrooms that is studied mainly as an immune-modulating add-on to cancer chemotherapy, where it is given by injection in a few countries. Evidence for oral supplements is limited, and quality varies widely between products. Talk with your pharmacist or doctor before using it, especially if you have a health condition or are pregnant or breastfeeding.
Other Drugs & Lentinan
Browse every other medication we’ve checked against Lentinan — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
813 interactions
- Diltiazem ›
- Theophylline ›
- Nifedipine ›
- Hydrocortisone ›
- Naproxen ›
- Erythromycin ›
- Estradiol ›
- Propranolol ›
- Lidocaine ›
- Norethindrone ›
- Testosterone ›
- Verapamil ›
- Levonorgestrel ›
- Prednisone ›
- Quinidine ›
- Cyclosporine ›
- Dexamethasone ›
- Triazolam ›
- Zopiclone ›
- Colchicine ›
- Fentanyl ›
- Oxybutynin ›
- Oxycodone ›
- Phenytoin ›
- Prednisolone ›
- Tacrolimus ›
- Temazepam ›
- Budesonide ›
- Carbamazepine ›
- Clindamycin ›
- Dextromethorphan ›
- Doxorubicin ›
- Fluticasone ›
- Formoterol ›
- Miconazole ›
- Morphine Sulfate ›
- Acetaminophen ›
- Amphetamine ›
- Buprenorphine ›
- Conjugated Estrogens ›
- Diazepam ›
- Everolimus ›
- Ivabradine ›
- Lofepramine ›
- Medroxyprogesterone ›
- Medroxyprogesterone Acetate ›
- Nortriptyline ›
- Propoxyphene ›
- Rifampin ›
- Testosterone Undecanoate ›
- Aripiprazole ›
- Bendamustine ›
- Caffeine (otc Drug) ›
- Ciclesonide ›
- Clonazepam ›
- Cyclobenzaprine ›
- Dapsone ›
- Desipramine ›
- Doxepin ›
- Duloxetine ›
Showing 60 of 813 moderate interactions — see all 813 on the Lentinan page.
No interaction 2,016 drugs checked — show the list
We also checked Lentinan against these medications and found no known interaction in our sources. Open any page to confirm.
- Levothyroxine ›
- Methylphenidate ›
- Ivermectin ›
- Aspirin ›
- Rosuvastatin ›
- Escitalopram ›
- Docusate ›
- Tirzepatide ›
- Ibuprofen ›
- Hydroxyurea ›
- Valacyclovir ›
- Sumatriptan ›
- Semaglutide ›
- Metformin ›
- Amoxicillin ›
- Lisinopril ›
- Isotretinoin ›
- Methotrexate ›
- Bupropion ›
- Doxycycline ›
- Acyclovir ›
- Azithromycin ›
- Lamotrigine ›
- Pregabalin ›
- Gabapentin ›
- Levothyroxine, Liothyronine ›
- Methylene Blue ›
- Ciprofloxacin ›
- Candesartan Cilexetil ›
- Amoxicillin, Clavulanate Potassium ›
- Acetaminophen, Dextromethorphan, Doxylamine ›
- Cyclopentolate ›
- Cephalexin ›
- Mannitol ›
- Roxithromycin ›
- Levetiracetam ›
- Ezetimibe ›
- Acetylsalicylic Acid ›
- Spironolactone ›
- Phentermine, Topiramate ›
- Dexmethylphenidate ›
- Levothyroxine Sodium ›
- Carbidopa, Levodopa ›
- Thyroid Hormone ›
- Pizotifen ›
- Valsartan ›
- Daptomycin ›
- Levodopa ›
- Hexobarbitone ›
- Lenvatinib ›
- Mitomycin ›
- Canagliflozin, Metformin ›
- Flutemetamol F-18 ›
- Magnesium Hydroxide (otc Drug) ›
- Insulin Degludec, Liraglutide ›
- Pegunigalsidase Alfa-iwxj ›
- Bentoquatam ›
- Cefaclor ›
- Sacubitril, Valsartan ›
- Alglucosidase Alpha ›
Showing the 60 most looked-up of 2,016 medications checked with no known interaction — see the full Lentinan 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, Guaifenesin, Phenylephrine Is Linked to Lower Levels of One Nutrient
Natural Medicines records Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine as a medicine that can lower these. This is not an interaction with Lentinan — 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 Lentinan and Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine Together: Common Questions
Can you take Lentinan with Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine?
Why are there 3 interactions listed for Lentinan and Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine?
How serious is the Lentinan and Acetaminophen, Dextromethorphan, Guaifenesin, Phenylephrine interaction?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
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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.