Ayahuasca + Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine
Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine brand names: Tylenol Cold Ex Strength, Children's Tylenol Cold Plus Cough.
Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine falls into 3 drug categories that Ayahuasca can interact with; the most serious is rated moderate. Theoretically, ayahuasca might increase levels of serotonin, which may have additive effects with serotonergic drugs.
Read the full interaction reportAyahuasca and Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine
These two interact in 3 distinct ways. Each one is explained separately below.
Why Are There 3 Interactions?
Ayahuasca interacts with whole categories of medication. Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine falls into 3 of those categories, so it can interact with Ayahuasca in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).
SEROTONERGIC DRUGS
1 of 3Why this applies to Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine
Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine falls under SEROTONERGIC DRUGS — the group Ayahuasca interacts with.
In vitro and animal research shows that harmaline and harmine, constituents of ayahuasca, strongly and reversibly inhibit monoamine oxidase A and weakly inhibit monoamine oxidase B. The dimethyltryptamine and tetrahydroharmine constituents of ayahuasca have also demonstrated serotonergic activity. A case of serotonin syndrome characterized by tremors, sweating, shivering, confusion, nausea, vomiting, and disorientation has been reported in a 36-year-old male who consumed 100 mL of ayahuasca while taking fluoxetine 20 mg daily. Combining serotonergic drugs with ayahuasca might increase the risk of serotonergic side effects including serotonin syndrome and cerebral vasoconstrictive disorders.
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 medicine has a few players, but the one I want to flag is the dextromethorphan (the cough suppressant). It nudges serotonin levels in the brain. Ayahuasca acts like an MAOI and also boosts serotonin, so pairing the two could stack up serotonin too high. That can lead to serotonin syndrome, with symptoms like shivering, sweating, tremors, a racing heart, agitation, confusion, and nausea.
On top of that, the pseudoephedrine is a stimulant, and combining stimulants with MAOI-type substances can dangerously spike blood pressure. This concern is based mostly on pharmacology and a few reports, not large studies, but the potential reaction is serious enough that I'd steer clear of mixing them. Please check with your pharmacist or doctor first.
- Kawanishi, K., Hashimoto, Y., Fujiwara, M., Kataoka, Y., and Ueki, S. Pharmacological characteristics of abnormal behavior induced by harmine with special reference to tremor in mice. J Pharmacobiodyn 1981;4(7):520-527. PubMed
- Herraiz, T., Gonzalez, D., Ancin-Azpilicueta, C., Aran, V. J., and Guillen, H. beta-Carboline alkaloids in Peganum harmala and inhibition of human monoamine oxidase (MAO). Food Chem Toxicol 2010;48(3):839-845. PubMed
- Fuller, R. W., Wong, C. J., and Hemrick-Luecke, S. K. MD 240928 and harmaline: opposite selectivity in antagonism of the inactivation of types A and B monoamine oxidase by pargyline in mice. Life Sci 1986;38(5):409-412. PubMed
- Abdel-Fattah, A. F., Matsumoto, K., Murakami, Y., Adel-Khalek, Gammaz H., Mohamed, M. F., and Watanabe, H. Central serotonin level-dependent changes in body temperature following administration of tryptophan to pargyline- and harmaline-pretreated rats. Ge PubMed
- Bergstrom, M., Westerberg, G., and Langstrom, B. 11C-harmine as a tracer for monoamine oxidase A (MAO-A): in vitro and in vivo studies. Nucl Med Biol 1997;24(4):287-293. PubMed
- Gerardy, J. Effect of moclobemide on rat brain monoamine oxidase A and B: comparison with harmaline and clorgyline. Prog Neuropsychopharmacol Biol Psychiatry 1994;18(4):793-802.
- Sacher, J., Houle, S., Parkes, J., Rusjan, P., Sagrati, S., Wilson, A. A., and Meyer, J. H. Monoamine oxidase A inhibitor occupancy during treatment of major depressive episodes with moclobemide or St. John's wort: an [11C]-harmine PET study. J Psychiatry
- dos Santos RG. Safety and side effects of ayahuasca in humans--an overview focusing on developmental toxicology. J Psychoactive Drugs. 2013 Jan-Mar;45(1):68-78. PubMed
- dos Santos RG. A critical evaluation of reports associating ayahuasca with life-threatening adverse reactions. J Psychoactive Drugs. 2013 Apr-Jun;45(2):179-88. PubMed
- Callaway JC, Grob CS. Ayahuasca preparations and serotonin reuptake inhibitors: a potential combination for severe adverse interactions. J Psychoactive Drugs. 1998 Oct-Dec;30(4):367-9. PubMed
CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES
2 of 3Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine also falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES.
Ayahuasca contains beta-carboline alkaloids, including harmine and harmaline. In vitro research suggests that the beta-carboline alkaloids might inhibit CYP2D6 enzymes. This effect has not been reported in humans.
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..
This cold-and-cough combo includes dextromethorphan, the cough suppressant, which your body clears using an enzyme called CYP2D6. Lab studies hint that the harmine and harmaline in ayahuasca may block that enzyme. If that happened, dextromethorphan could build up and lead to more dizziness, drowsiness, or in higher amounts strange feelings or confusion.
There's a bigger concern here, though. The beta-carbolines in ayahuasca act like MAOIs, and mixing MAOIs with dextromethorphan (and the pseudoephedrine decongestant) can raise the risk of serotonin syndrome and dangerous blood pressure spikes. That combination is one to genuinely avoid. The CYP2D6 part is only theoretical and from lab work, but please talk with your pharmacist or doctor before combining these.
- Zhao, T., He, Y. Q., Wang, J., Ding, K. M., Wang, C. H., and Wang, Z. T. Inhibition of human cytochrome P450 enzymes 3A4 and 2D6 by β-carboline alkaloids, harmine derivatives. Phytother Res 2011;25(11):1671-1677.
- dos Santos RG. Safety and side effects of ayahuasca in humans--an overview focusing on developmental toxicology. J Psychoactive Drugs. 2013 Jan-Mar;45(1):68-78. PubMed
CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES
3 of 3Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.
Ayahuasca contains beta-carboline alkaloids. In vitro research suggests that beta-carboline alkaloids competitively inhibit CYP3A4 enzymes. This effect 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 has several ingredients, and a couple of them lean on the liver's CYP3A4 pathway to break down. The lab research here suggests the beta-carboline compounds in ayahuasca can block CYP3A4. If that happened in the body, ingredients like dextromethorphan could build up, meaning more drowsiness, dizziness, or even confusing, agitated feelings.
There's a bigger concern I want to flag separately: ayahuasca acts like an MAO inhibitor, and mixing MAOIs with dextromethorphan or pseudoephedrine can cause dangerous reactions like serotonin syndrome or a spike in blood pressure. The CYP3A4 part is only theoretical (lab data, not seen in people), but the MAOI risk is real. Please check with your pharmacist or doctor before combining these.
- Zhao, T., He, Y. Q., Wang, J., Ding, K. M., Wang, C. H., and Wang, Z. T. Inhibition of human cytochrome P450 enzymes 3A4 and 2D6 by β-carboline alkaloids, harmine derivatives. Phytother Res 2011;25(11):1671-1677.
- dos Santos RG. Safety and side effects of ayahuasca in humans--an overview focusing on developmental toxicology. J Psychoactive Drugs. 2013 Jan-Mar;45(1):68-78. 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.
Ayahuasca Also Interacts With Other Medications
Ayahuasca has 803 moderate known drug interactions in our database — the Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine one above is among them. If you take anything else, check it against the full list below.
Check Another of Your Medications Against Ayahuasca
We haven’t checked that one against Ayahuasca yet — ask our pharmacists directly.
Covers the 2,830 medications we’ve checked against Ayahuasca. Pick one to open its full report.
See Every Supplement That Interacts With Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine
This page covers Ayahuasca only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine page lists 301 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 · 242 moderate · 45 minor.
From our pharmacist’s overview on the Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine page
“Because Tylenol Cold Extra Strength packs four drugs into one dose (acetaminophen, chlorpheniramine, dextromethorphan, and pseudoephedrine), its supplement list runs to 301 ingredients, and 14 carry a major rating, so I'd approach this one with real care. The biggest hazards mirror the drugs themselves.”
Reviewed by 2 · Jul 18, 2026
Open the Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine interaction page
Where Ayahuasca and Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine 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.
#743 of 1,452 supplements looked up here in the last 7 days
#1,178 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 Ayahuasca
What is Ayahuasca?
- Spiritual and ceremonial rituals
- Depression
- Anxiety
- Substance use disorders
- Personal or emotional insight
Ayahuasca is a powerful psychoactive brew that combines a DMT-containing plant with a vine that allows the DMT to take effect, causing intense hallucinations. It is illegal in many places, can trigger dangerous reactions, and is not recommended for self-use; talk to a doctor or pharmacist before considering it.
Other Drugs & Ayahuasca
Browse every other medication we’ve checked against Ayahuasca — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
803 interactions
- Diltiazem ›
- Nifedipine ›
- Hydrocortisone ›
- Methylphenidate ›
- Erythromycin ›
- Estradiol ›
- Propranolol ›
- Lidocaine ›
- Norethindrone ›
- Testosterone ›
- Verapamil ›
- Levonorgestrel ›
- Prednisone ›
- Quinidine ›
- Cyclosporine ›
- Dexamethasone ›
- Triazolam ›
- Zopiclone ›
- Colchicine ›
- Fentanyl ›
- Oxybutynin ›
- Oxycodone ›
- Prednisolone ›
- Tacrolimus ›
- Temazepam ›
- Apomorphine ›
- Budesonide ›
- Carbamazepine ›
- Clindamycin ›
- Dextromethorphan ›
- Doxorubicin ›
- Fluticasone ›
- Formoterol ›
- Miconazole ›
- Morphine Sulfate ›
- Phenylephrine ›
- Trimipramine ›
- Amphetamine ›
- Buprenorphine ›
- Conjugated Estrogens ›
- Diazepam ›
- Everolimus ›
- Ivabradine ›
- Lofepramine ›
- Medroxyprogesterone ›
- Medroxyprogesterone Acetate ›
- Nortriptyline ›
- Propoxyphene ›
- Rifampin ›
- Selegiline ›
- Sumatriptan Succinate ›
- Testosterone Undecanoate ›
- Aripiprazole ›
- Caffeine (otc Drug) ›
- Ciclesonide ›
- Clonazepam ›
- Cyclobenzaprine ›
- Dapsone ›
- Desipramine ›
- Doxepin ›
Showing 60 of 803 moderate interactions — see all 803 on the Ayahuasca page.
No interaction 2,026 drugs checked — show the list
We also checked Ayahuasca against these medications and found no known interaction in our sources. Open any page to confirm.
- Levothyroxine ›
- Ivermectin ›
- Aspirin ›
- Rosuvastatin ›
- Acetaminophen ›
- Docusate ›
- Hydroxyurea ›
- Valacyclovir ›
- Ibuprofen ›
- Tirzepatide ›
- Semaglutide ›
- Metformin ›
- Lisinopril ›
- Amoxicillin ›
- Bupropion ›
- Bendamustine ›
- Acyclovir ›
- Methotrexate ›
- Doxycycline ›
- Lamotrigine ›
- Pregabalin ›
- Azithromycin ›
- Gabapentin ›
- Isotretinoin ›
- Naproxen ›
- Ciprofloxacin ›
- Levothyroxine, Liothyronine ›
- Candesartan Cilexetil ›
- Cephalexin ›
- Cyclopentolate ›
- Acetaminophen, Dextromethorphan, Doxylamine ›
- Roxithromycin ›
- Mannitol ›
- Levetiracetam ›
- Pegunigalsidase Alfa-iwxj ›
- Ezetimibe ›
- Daptomycin ›
- Levothyroxine Sodium ›
- Mitomycin ›
- Valsartan ›
- Spironolactone ›
- Amoxicillin, Clavulanate Potassium ›
- Hexobarbitone ›
- Phentermine, Topiramate ›
- Thyroid Hormone ›
- Acetaminophen, Ibuprofen ›
- Factor 7a ›
- Acetaminophen, Aspirin ›
- Hethylphenidate Hcl ›
- Minoxidil ›
- Lenvatinib ›
- Cefaclor ›
- Azelaic Acid ›
- Ibuprofen, Acetaminophen ›
- Hydroxychloroquine ›
- Tenecteplase ›
- Dirithromycin ›
- Vancomycin ›
- Pizotifen ›
- Triptorelin ›
Showing the 60 most looked-up of 2,026 medications checked with no known interaction — see the full Ayahuasca 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, Chlorpheniramine, Dextromethorphan, Pseudoephedrine Is Linked to Lower Levels of One Nutrient
Natural Medicines records Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine as a medicine that can lower these. This is not an interaction with Ayahuasca — 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 Ayahuasca and Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine Together: Common Questions
Can you take Ayahuasca with Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine?
Why are there 3 interactions listed for Ayahuasca and Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine?
How serious is the Ayahuasca and Acetaminophen, Chlorpheniramine, Dextromethorphan, Pseudoephedrine 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.