Ceylon Leadwort + Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine
Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine brand name: Colrex.
Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine falls into 4 drug categories that Ceylon Leadwort can interact with; the most serious is rated moderate. Plumbagin, a constituent of Ceylon leadwort, has been shown to inhibit cytochrome P450 2D6 (CYP2D6) in vitro.
Read the full interaction reportCeylon Leadwort and Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine
These two interact in 4 distinct ways. Each one is explained separately below.
Why Are There 4 Interactions?
Ceylon Leadwort interacts with whole categories of medication. Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine falls into 4 of those categories, so it can interact with Ceylon Leadwort in 4 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).
CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES
1 of 4Why this applies to Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine
Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES — the group Ceylon Leadwort interacts with.
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 wrinkle with this combo product: the codeine piece is a prodrug. Your body uses an enzyme called CYP2D6 to turn codeine into morphine, which is what actually relieves pain and quiets a cough. Plumbagin, a compound in Ceylon Leadwort, has been shown in lab dishes only to block CYP2D6. If that held true in people, less codeine would convert to morphine, so you might get weaker pain and cough relief rather than more.
The good news is this is theoretical, based on test-tube data, with nothing reported in real patients, so I wouldn't lose sleep over it. Still, since the direction is hard to predict, run it by your pharmacist or doctor before pairing the two.
- Chen A, Zhou X, Tang S, Liu M, Wang X. Evaluation of the inhibition potential of plumbagin against cytochrome P450 using LC-MS/MS and cocktail approach. Sci Rep. 2016 Jun 22;6:28482. PubMed
CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES
2 of 4Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine also falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES.
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 thing to know about this combo. Ceylon Leadwort contains plumbagin, which in lab dishes slowed down a liver enzyme called CYP1A2. None of the ingredients in Colrex (acetaminophen, chlorpheniramine, codeine, and phenylephrine) lean heavily on CYP1A2, so this particular interaction is mostly theoretical and hasn't been seen in real people. The evidence here is weak, based only on test-tube work.
I wouldn't lose sleep over it, but I'd still mention it to your pharmacist, especially since this product already adds up several active ingredients. Codeine can cause drowsiness and constipation, chlorpheniramine adds to that sleepiness, and stacking an unproven herb on top isn't worth the guesswork. When in doubt, ask before combining.
- Chen A, Zhou X, Tang S, Liu M, Wang X. Evaluation of the inhibition potential of plumbagin against cytochrome P450 using LC-MS/MS and cocktail approach. Sci Rep. 2016 Jun 22;6:28482. PubMed
CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES
3 of 4Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine also falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES.
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 combination cold and pain product has a wrinkle worth knowing about. One ingredient, codeine, is a prodrug, meaning your body has to convert it into its active painkilling form. That activation mainly runs through a different enzyme (CYP2D6), but CYP3A4 also handles part of codeine's breakdown, and it helps clear the acetaminophen and chlorpheniramine in the mix too.
In lab dishes, plumbagin from Ceylon Leadwort slowed CYP3A4. This has never actually been seen in people, so it's theoretical. If it did happen, levels of these ingredients could edge up, possibly meaning more drowsiness, constipation, or dizziness. Since the evidence is weak, don't panic, but do run it by your pharmacist or doctor before pairing them.
- Chen A, Zhou X, Tang S, Liu M, Wang X. Evaluation of the inhibition potential of plumbagin against cytochrome P450 using LC-MS/MS and cocktail approach. Sci Rep. 2016 Jun 22;6:28482. PubMed
CYTOCHROME P450 2E1 (CYP2E1) SUBSTRATES
4 of 4Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine also falls under CYTOCHROME P450 2E1 (CYP2E1) SUBSTRATES.
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 (Colrex) contains acetaminophen for pain and fever, plus an antihistamine, codeine, and a decongestant. The piece that matters here is the acetaminophen. A compound in Ceylon Leadwort called plumbagin has slowed down an enzyme called CYP2E1 in lab dishes. That enzyme is one pathway your liver uses to handle acetaminophen, so in theory blocking it could shift how the drug is processed.
I want to be honest about the strength of this: it has only been seen in test-tube and animal studies, never confirmed in real people, so it may not matter much in everyday life. Still, since acetaminophen and the liver are involved, it's worth a quick chat with your pharmacist before pairing them, especially if you drink alcohol or take other acetaminophen products.
- Chen A, Zhou X, Tang S, Liu M, Wang X. Evaluation of the inhibition potential of plumbagin against cytochrome P450 using LC-MS/MS and cocktail approach. Sci Rep. 2016 Jun 22;6:28482. 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.
Ceylon Leadwort Also Interacts With Other Medications
Ceylon Leadwort has 1,096 moderate known drug interactions in our database — the Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine one above is among them. If you take anything else, check it against the full list below.
Check Another of Your Medications Against Ceylon Leadwort
We haven’t checked that one against Ceylon Leadwort yet — ask our pharmacists directly.
Covers the 2,830 medications we’ve checked against Ceylon Leadwort. Pick one to open its full report.
See Every Supplement That Interacts With Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine
This page covers Ceylon Leadwort only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine page lists 338 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), Asarabacca (major), Beer (major) and Ephedra (major).
By severity: 18 major · 275 moderate · 45 minor.
From our pharmacist’s overview on the Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine page
“Someone taking Colrex is usually fighting a miserable cold, and cold season is also when people reach for herbal sleep aids and energy boosters, which is exactly where this list bites hardest. Colrex combines acetaminophen, chlorpheniramine, codeine, and phenylephrine, and 18 of its 338 supplement interactions rate major, enough to war…”
Reviewed by 2 · Jul 18, 2026
Open the Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine interaction page
Taking Ceylon Leadwort as Part of a Dietary Supplement Product? Check It for Interactions
We hold 96 real supplement products containing Ceylon Leadwort, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Ceylon Leadwort. Your product may carry other ingredients that interact with Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine too, on top of Ceylon Leadwort — and those would not show on this page. Find your product and we’ll check every ingredient on its label:
Where Ceylon Leadwort and Acetaminophen, Chlorpheniramine, Codeine, 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.
#548 of 1,452 supplements looked up here in the last 7 days
#252 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 Ceylon Leadwort
What is Ceylon Leadwort?
- Digestive complaints and poor appetite
- Skin conditions and wounds (applied to the skin)
- Joint pain and swelling
- Traditional 'metabolism-boosting' tonics
- Antimicrobial folk remedy
Ceylon Leadwort (Plumbago zeylanica) is a plant long used in Ayurvedic and other traditional medicine systems, mainly for digestion, skin problems, and pain. Solid human studies are lacking, and the plant contains plumbagin, a compound that can irritate skin and tissues and may be unsafe in larger amounts. Talk to a pharmacist or doctor before using it, and avoid it in pregnancy.
Other Drugs & Ceylon Leadwort
Browse every other medication we’ve checked against Ceylon Leadwort — both the ones with a known interaction and the ones without. Select any drug for the full detail.
No drugs match “”.
1,096 interactions
- Diclofenac Sodium ›
- Diltiazem ›
- Theophylline ›
- Nifedipine ›
- Ibuprofen ›
- Aspirin ›
- Hydrocortisone ›
- Insulin (rdna) ›
- Naproxen ›
- Erythromycin ›
- Estradiol ›
- Minocycline ›
- Propranolol ›
- Lidocaine ›
- Norethindrone ›
- Testosterone ›
- Verapamil ›
- Levonorgestrel ›
- Prednisone ›
- Quinidine ›
- Cyclosporine ›
- Dexamethasone ›
- Glyburide ›
- Insulin (pork) ›
- Triazolam ›
- Zopiclone ›
- Bupropion ›
- Colchicine ›
- Fentanyl ›
- Flurbiprofen ›
- Orphenadrine ›
- Oxybutynin ›
- Oxycodone ›
- Phenytoin ›
- Prednisolone ›
- Tacrolimus ›
- Temazepam ›
- Triamcinolone ›
- Budesonide ›
- Carbamazepine ›
- Clindamycin ›
- Dextromethorphan ›
- Diclofenac Potassium ›
- Dipyridamole ›
- Doxorubicin ›
- Fluticasone ›
- Formoterol ›
- Indomethacin ›
- Insulin (human) ›
- Miconazole ›
- Morphine Sulfate ›
- Trimipramine ›
- Acetaminophen ›
- Amphetamine ›
- Buprenorphine ›
- Conjugated Estrogens ›
- Diazepam ›
- Everolimus ›
- Ivabradine ›
- Ketoprofen ›
Showing 60 of 1,096 moderate interactions — see all 1,096 on the Ceylon Leadwort page.
No interaction 1,733 drugs checked — show the list
We also checked Ceylon Leadwort against these medications and found no known interaction in our sources. Open any page to confirm.
- Levothyroxine ›
- Methylphenidate ›
- Ivermectin ›
- Rosuvastatin ›
- Escitalopram ›
- Docusate ›
- Valacyclovir ›
- Hydroxyurea ›
- Sumatriptan ›
- Amoxicillin ›
- Acyclovir ›
- Lisinopril ›
- Doxycycline ›
- Methotrexate ›
- Lamotrigine ›
- Gabapentin ›
- Pregabalin ›
- Azithromycin ›
- Isotretinoin ›
- Methylene Blue ›
- Ciprofloxacin ›
- Levothyroxine, Liothyronine ›
- Cyclopentolate ›
- Candesartan Cilexetil ›
- Cephalexin ›
- Mannitol ›
- Roxithromycin ›
- Acetaminophen, Dextromethorphan, Doxylamine ›
- Pegunigalsidase Alfa-iwxj ›
- Daptomycin ›
- Hexobarbitone ›
- Levothyroxine Sodium ›
- Dexmethylphenidate ›
- Levetiracetam ›
- Spironolactone ›
- Factor 7a ›
- Carbidopa, Levodopa ›
- Thyroid Hormone ›
- Minoxidil ›
- Mitomycin ›
- Levodopa ›
- Ezetimibe ›
- Cefaclor ›
- Lenvatinib ›
- Phenylephrine ›
- Vancomycin ›
- Hethylphenidate Hcl ›
- Phentermine, Topiramate ›
- Dirithromycin ›
- Bentoquatam ›
- Procainamide ›
- Amoxicillin, Clavulanate Potassium ›
- Hydroxychloroquine ›
- Digoxin ›
- Azelaic Acid ›
- Dextrothyroxine ›
- Triptorelin ›
- Lomustine ›
- Sodium Valproate ›
- Hydrochlorothiazide ›
Showing the 60 most looked-up of 1,733 medications checked with no known interaction — see the full Ceylon Leadwort 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, Codeine, Phenylephrine Is Linked to Lower Levels of One Nutrient
Natural Medicines records Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine as a medicine that can lower these. This is not an interaction with Ceylon Leadwort — it is a separate effect of the medicine, and it is a reason some people are advised to supplement rather than to avoid one:
Read the full Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine nutrient depletion report ›
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 Ceylon Leadwort and Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine Together: Common Questions
Can you take Ceylon Leadwort with Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine?
Why are there 4 interactions listed for Ceylon Leadwort and Acetaminophen, Chlorpheniramine, Codeine, Phenylephrine?
How serious is the Ceylon Leadwort and Acetaminophen, Chlorpheniramine, Codeine, 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.