Herb & supplement monograph

Cinchona Drug Interactions, Uses, Effectiveness, Safety & More

Medically reviewed by ·Updated July 2026
What is this page for?

First and foremost: how Cinchona interacts with medications. The heart of this page is the interaction list — every drug Cinchona is known to interact with, and how serious each one is.

But these pages have grown well beyond that into a full monograph — what Cinchona is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy

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Cinchona Drug Interactions: The Bottom Line

From the HelloPharmacist Editorial Team · Updated July 2026

Based on the available evidence, the overall risk of a clinically significant Cinchona drug interaction is moderate for most people, so this supplement calls for more caution than many others. Nearly all of its many listed interactions are rated moderate, and a few, tied to the quinine and quinidine it naturally contains, are rated major.

Interactions deserving the most attention

Because cinchona contains quinine and quinidine, taking it alongside prescription quinidine or quinine could raise levels and side effects of those medicines. The strongest human evidence involves carbamazepine, where a cinchona constituent raised drug levels, and a similar effect is reported with phenobarbital, so seizure medicine levels could shift. There are also theoretical concerns with digoxin, blood thinners, and medicines that can affect heart rhythm.

What the rest of the list means

The list is long mainly because cinchona's alkaloids may block an enzyme the body uses to clear many common medications and may affect the heart's electrical rhythm, so a large number of drugs are flagged on theory alone. Most of these predictions come from lab research rather than harm shown in people, so many combinations may never cause a noticeable problem.

Check your medications against Cinchona

Based on HelloPharmacist’s Cinchona interaction data and reviewed under our editorial standards.

Interaction report

Drugs that interact with Cinchona

492 medications have a known interaction with Cinchona, graded by severity. Select any drug for the full evidence-based detail.

3 major interactions. These combinations can be clinically significant — best avoided, or used only with close professional supervision. Always check with your pharmacist before combining them with Cinchona.

2,830 drugs
QuinidineCardioquin, Cin-Quin, Duraquin, Lin-Qin, Quinova, Quinaglute, Quinaglute Duratabs +2 more› QuinineQualaquin› Quinine SulfateQuinamm, Quinine Sulfate› AbciximabReoPro› AbrocitinibCibinqo› AcenocoumarolSintrom› Acetaminophen, AspirinGemnisyn› Acetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine› Acetaminophen, Butalbital, Caffeine, CodeineEsgic with Codeine, Fioricet w/ Codeine› Acetaminophen, Butalbital, CodeineBancap w/ Codeine› Acetaminophen, Butalbital, Codeine PhosphatePhrenilin #3› Acetaminophen, Caffeine, Chlorpheniramine, Hydrocodone, PhenylephrineHycomine Compound› Acetaminophen, Caffeine, CodeineGesic C15, Gesic C30, Gesic C8, Lenoltec 1, Lenoltec 2, Lenoltec 3 +1 more› Acetaminophen, Caffeine, Codeine, SalicylamideCodalan No.1, Codalan No.2, Codalan No.3› Acetaminophen, Caffeine, DihydrocodeineDHC Plus, Panlor DC, Panlor SS› Acetaminophen, Chlorpheniramine Maleate, Dextromethorphan HbrVicks Formula 44M Cough, Cold & Flu Relief› Acetaminophen, Chlorpheniramine, Codeine, PhenylephrineColrex› Acetaminophen, Chlorpheniramine, DextromethorphanCoricidin II Extra Strength Cold and Flu› Acetaminophen, Chlorpheniramine, Dextromethorphan HydrobromideCoricidin HBP Maximum Strength Flu› Acetaminophen, Chlorpheniramine, Dextromethorphan, PhenylpropanolamineMulti Symptom Cold Relief› Acetaminophen, Chlorpheniramine, Dextromethorphan, PseudoephedrineChildren's Tylenol Cold Plus Cough, Tylenol Cold Ex Strength› Acetaminophen, Chlorzoxazone, CodeineAcetazone Forte C8, Parafon Forte C8› Acetaminophen, CodeineTylenol No.3, Tylenol w/ Codeine› Acetaminophen, Codeine, DoxylamineMersyndol› Acetaminophen, Codeine, MethocarbamolAcetaminophen, Codeine, Methocarbamol, Robaxacet 8› Acetaminophen, DextromethorphanTylenol Cough Ex Strength› Acetaminophen, Dextromethorphan, Doxylamine, PseudoephedrineVicks NyQuil› Acetaminophen, Dextromethorphan, Guaifenesin, PhenylephrineConar-A› Acetaminophen, Dextromethorphan, Guaifenesin, PhenylpropanolamineAnatuss› Acetaminophen, Dextromethorphan, Guaifenesin, PseudoephedrineRobitussin Cold, Severe Cold, Suphedrine Cold/Cough›
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 drug listed above links to the full report for that exact Cinchona combination — clinical detail, likelihood, evidence level, and citations.
  • Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
The big picture

The kinds of drugs Cinchona affects

Every type of medication (drug category) Cinchona is known to interact with. Open any category for the detail — or search your exact drug in the checker above.

All 11 drug categories Cinchona interacts with
QuinidineQuinineAntacidsAnticoagulant/antiplatelet DrugsCarbamazepine (tegretol)Cytochrome P450 2d6 (cyp2d6) SubstratesDigoxin (lanoxin)Phenobarbital (luminal)Qt Interval-prolonging DrugsH2-blockersProton Pump Inhibitors (ppis)
Quinidine

Theoretically, taking cinchona might increase plasma levels and adverse effects of quinidine.
Cinchona contains quinidine.

Likelihood Probable Evidence D
Quinine

Theoretically, taking cinchona might increase plasma levels and adverse effects of quinine.
Cinchona contains quinine.

Likelihood Probable Evidence D
Antacids

Theoretically, taking cinchona might decrease the effectiveness of antacids. Theoretically, taking antacids might also increase the risk of adverse effects from cinchona.
Some research shows that taking cinchona lowers stomach acid pH. In addition, some research shows that taking antacids might increase urinary pH. Theoretically, this may increase the amount of quinidine, a constituent of cinchona, reabsorbed in the renal tubules and increase the risk of quinidine toxicity.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, taking cinchona might increase the drug effects and risk of bleeding with anticoagulant and antiplatelet drugs.
In vitro evidence shows that the alkaloids quinine, quinidine, and cinchonine, constituents of cinchona, inhibit platelet aggregation.

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

Theoretically, taking cinchona might increase the adverse effects of carbamazepine.
Clinical research shows that taking quinine, a constituent of cinchona, increases the peak plasma concentration and area under the curve of carbamazepine.

Likelihood Probable Evidence B
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, taking cinchona might inhibit cytochrome P450 2D6 (CYP2D6) and increase levels of drugs metabolized by this enzyme.
Quinidine, a constituent of cinchona, inhibits CYP2D6-mediated metabolism in humans.

Likelihood Possible Evidence D
Digoxin (Lanoxin)

Theoretically, taking cinchona might increase serum levels of digoxin.
Quinine and quinidine, which are constituents of cinchona, decrease clearance of digoxin and increase serum digoxin levels in humans.

Likelihood Possible Evidence D
Phenobarbital (Luminal)

Theoretically, taking cinchona might increase the adverse effects of phenobarbital.
Clinical research shows that taking quinine, a constituent of cinchona, increases the peak plasma concentration and area under the curve of phenobarbital.

Likelihood Probable Evidence D
Qt Interval-Prolonging Drugs

Theoretically, taking cinchona with other QT interval-prolonging drugs might cause an additive effect and increase the risk of ventricular arrhythmias.
Quinidine and quinine, which are constituents of cinchona, prolong the QT interval.

Likelihood Possible Evidence D
H2-Blockers

Theoretically, taking cinchona might decrease the effectiveness of H2-blockers.
Some research shows that taking cinchona lowers stomach acid pH.

Likelihood Possible Evidence D
Proton Pump Inhibitors (Ppis)

Theoretically, taking cinchona might decrease the effectiveness of PPIs.
Some research shows that taking cinchona lowers stomach acid pH.

Likelihood Possible Evidence D
Monograph

Cinchona: Uses, Safety & Side Effects

Medically reviewed by · Reviewed July 2026 ·
The bottom line

Cinchona bark is the natural source of quinine and has been used for centuries to treat malaria and fever, but the bark itself is not standardized and can be unpredictable and risky. Modern medicine uses purified, dose-controlled quinine instead, and the supplement form carries real dangers, including serious heart and blood problems. Talk to a pharmacist or doctor before using it, and avoid it during pregnancy.

Cinchona
Scientific name
Cinchona officinalis
Family
Rubiaceae
Part used
Bark
Common forms
Dried bark, tinctures, liquid extracts, capsules, teas, and as a bitter flavoring in tonic water
People commonly use it for
  • Malaria (historical/traditional)
  • Fever
  • Leg cramps and restless legs
  • Digestive upset and loss of appetite
  • Bitter tonic

Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.

Safety at a glance
OverallUse caution

Contains quinine, which can cause serious side effects, and the bark is not dose-controlled.

PregnancyLikely Unsafe

When used orally. Cinchona is reported to have uterine stimulant and abortifacient activity, and to be fetotoxic and teratogenic, causing visual and a...

Read the full pregnancy detail
BreastfeedingPossibly Unsafe

When used orally. The cinchona alkaloids quinine and quinidine are reported to be excreted in breast milk and may be toxic to infants.

Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Jump to a section

Overview

Cinchona is a group of evergreen trees and shrubs in the coffee family (Rubiaceae). They are native to the Andes mountains of South America and are now also grown in other tropical regions. The part used in medicine is the dried bark.

Cinchona bark is most famous as the natural source of quinine, a compound that has been used for hundreds of years to treat malaria and fevers. The bark also has a strong bitter taste, which is why small amounts of quinine are used to flavor tonic water and some alcoholic drinks.

In traditional medicine, cinchona bark has been used for fever, muscle cramps, restless legs, digestive complaints, and as a bitter "tonic" to stimulate appetite. Today, doctors use purified, carefully measured quinine instead of the raw bark.

How it works

Cinchona bark contains a mix of compounds called quinoline alkaloids, including quinine, quinidine, cinchonine, and cinchonidine. Quinine is the best known and is the main reason the bark has been valued.

Quinine is believed to work against malaria parasites by interfering with how the parasite handles a toxic byproduct of the blood it consumes. Quinidine, a related alkaloid, can affect the rhythm of the heart. The bitter compounds may stimulate digestive juices and appetite, which is why cinchona was used as a bitter tonic.

Because the bark naturally contains several active alkaloids in varying amounts, its effects can be hard to predict compared with a purified, standardized medicine.

Effectiveness

Does Cinchona work?

Here’s what the research actually shows for each use — graded by Natural Medicines and reviewed by .

Evidence overview · 8 uses evaluated
8 Insufficient evidence
How to read these evidence grades

Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.

1EffectiveStrong, consistent evidence it works.
2Likely EffectiveGood evidence, though not yet conclusive.
3Possibly EffectiveSome evidence suggests a benefit.
4Possibly IneffectiveSome evidence it may not help.
5Likely IneffectiveFairly strong evidence it doesn’t help.
6IneffectiveStrong evidence it doesn’t work.
7Insufficient Reliable Evidence to RateToo little research to say either way.

For Cinchona, current evidence isn’t strong enough to rate any specific use. The conditions it has been studied for are listed below.

Also studied for 8 conditions — evidence insufficient to rate
Insufficient Reliable Evidence To Rate Cancer
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral cinchona for cancer, there is insufficient reliable information about the clinical effects of cinchona for this purpose.

Insufficient Reliable Evidence To Rate Hemorrhoids
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral or topical cinchona for hemorrhoids, there is insufficient reliable information about the clinical effects of cinchona for this purpose.

Insufficient Reliable Evidence To Rate Influenza
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral cinchona for influenza, there is insufficient reliable information about the clinical effects of cinchona for this purpose.

Insufficient Reliable Evidence To Rate Leg cramps
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral cinchona for leg cramps, there is insufficient reliable information about the clinical effects of cinchona for this purpose.

Insufficient Reliable Evidence To Rate Malaria
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral cinchona for malaria, there is insufficient reliable information about the clinical effects of cinchona for this purpose.

Insufficient Reliable Evidence To Rate Muscle cramps
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral cinchona for muscle cramps, there is insufficient reliable information about the clinical effects of cinchona for this purpose.

Insufficient Reliable Evidence To Rate Respiratory tract infections
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral cinchona for respiratory tract infections, there is insufficient reliable information about the clinical effects of cinchona for this purpose.

Insufficient Reliable Evidence To Rate Varicose veins
Rating & evidence shown verbatim from Natural Medicines

Although there has been interest in using oral or topical cinchona for varicose veins, there is insufficient reliable information about the clinical effects of cinchona for this purpose.

Source & disclaimer. Effectiveness ratings and evidence summaries are provided by Natural Medicines (Therapeutic Research Center) and shown as licensed. Where Natural Medicines hasn’t rated a use, HelloPharmacist’s pharmacists may add their own reviewed rating and evidence (each such entry is labeled). This is educational information, not medical advice — talk with your pharmacist or doctor before starting, stopping, or changing a supplement.

Safety & precautions

Cinchona should be used with real caution. Because it contains quinine and related alkaloids, it can cause the same kinds of problems that prescription quinine can, including serious effects on the heart, blood, and hearing. The amount of active compound in bark products is not standardized, which adds to the risk.

People with heart rhythm problems, low platelets or other blood disorders, ringing in the ears, vision problems, certain enzyme deficiencies (such as G6PD deficiency), or kidney or liver disease should not use cinchona without medical advice. Anyone who has had a bad reaction to quinine or tonic water should also avoid it.

Pregnancy: Avoid cinchona during pregnancy. Quinine may affect the pregnancy and is not considered safe in supplement form. Breastfeeding: Avoid it, since safety has not been established and quinine can pass into breast milk. Always check with a pharmacist or doctor before using cinchona.

Side effects

A group of symptoms linked to quinine is sometimes called cinchonism. This can include ringing in the ears, headache, nausea, dizziness, blurred vision, and flushing. These often happen with higher doses.

More serious but less common effects can include heart rhythm changes, a sudden drop in platelets (which can cause unusual bruising or bleeding), severe allergic reactions, and dangerous reactions affecting the blood. Some people develop these reactions even after small amounts of quinine.

If you have signs of a serious reaction, such as easy bruising or bleeding, a fast or irregular heartbeat, fainting, severe rash, or trouble breathing, stop using it and seek medical care right away.

Cinchona: Reported Adverse Effects

Documented safety reports on Cinchona from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.

Information on the adverse effects of cinchona is limited. Orally, prolonged use of high doses of cinchona can cause severe adverse effects. Topically, a thorough evaluation of safety outcomes has not been conducted.

Most Common Adverse Effects:

Orally: Diarrhea, nausea, ringing ears, vomiting.

Topically: Contact dermatitis, urticaria.

Serious Adverse Effects (Rare):

Orally: Arrhythmias, cinchonism syndrome, hemolytic uremic syndrome, QT prolongation, thrombotic thrombocytopenic purpura.

Reports by condition
Anemia Hematologic

Quinine, which is present in cinchona, has been associated with serious, sometimes fatal, hematological disorders including thrombocytopenia, thrombotic thrombocytopenic purpura (TTP), and hemolytic uremic syndrome (hemolytic anemia, acute renal failure, and thrombocytopenia). Initial symptoms may include bleeding from the gums, nose or gastrointestinal tract, easy bruising, and petechiae. Bone marrow depression and thrombocytopenia have also been associated with quinidine.

  1. US Food and Drug Administration notice: Drug products containing quinine - enforcement action dates. Docket # 2006N-0476. Federal Register 2006 (December 15);71 (241): 75557-60.
  2. FDA Drug Safety Communication: New risk management plan and patient medication guide for Qualaquin (quinine sulfate). 07-08-2010. https://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm218202 (accessed 02/18/17).
  3. Hardman JG, Limbird LL, Molinoff PB, eds. Goodman and Gillman's The Pharmacological Basis of Therapeutics, 9th ed. New York, NY: McGraw-Hill, 1996.
Arrhythmia Cardiovascular

Cinchona contains the alkaloids quinidine and quinine that can prolong the QT interval on the electrocardiogram, and cause potentially fatal cardiac arrhythmias such as torsades de pointes

  1. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  2. US Food and Drug Administration notice: Drug products containing quinine - enforcement action dates. Docket # 2006N-0476. Federal Register 2006 (December 15);71 (241): 75557-60.
Arrhythmia Other

Orally, prolonged use of high doses of cinchona or its alkaloids, or a single dose of 3 grams or more of the alkaloid quinine are associated with a toxicity syndrome known as cinchonism. Symptoms include headache, dizziness, nausea and vomiting, diarrhea, hemolysis, hypotension, cardiac arrhythmias, tinnitus, deafness, vision changes, blindness, abdominal pain, delirium, convulsions, paralysis, and collapse. Doses of 10-15 grams of quinine may be fatal.

  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  3. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  4. Hardman JG, Limbird LL, Molinoff PB, eds. Goodman and Gillman's The Pharmacological Basis of Therapeutics, 9th ed. New York, NY: McGraw-Hill, 1996.
  5. US Food and Drug Administration notice: Drug products containing quinine - enforcement action dates. Docket # 2006N-0476. Federal Register 2006 (December 15);71 (241): 75557-60.
  6. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
Dermatitis Dermatologic

Topical use of cinchona bark extracts and occupational exposure to cinchona bark dust can cause contact dermatitis and other urticarial reactions. A 31-year old man developed itching, erythema, and edema of the face and upper chest after occupational exposure to dust from cinchona bark. Skin testing produced reactions to ethanol and ether extracts of the bark, but not to the individual alkaloids quinine and quinidine.

  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. Dooms-Goossens A, Deveylder H, Duron C, et al. Airborne contact urticaria due to cinchona. Contact Dermatitis 1986;15(4):258.
Diarrhea Gastrointestinal

Cinchona stimulates secretion of stomach acid and has been associated with nausea, vomiting, and diarrhea.

  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
Tinnitus Ocular/Otic

Cinchona contains quinine that can cause dose-related adverse effects on hearing and vision, including tinnitus, deafness, vision changes, and blindness.

  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Wichtl MW. Herbal Drugs and Phytopharmaceuticals. Ed. N.M. Bisset. Stuttgart: Medpharm GmbH Scientific Publishers, 1994.
  3. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  4. US Food and Drug Administration notice: Drug products containing quinine - enforcement action dates. Docket # 2006N-0476. Federal Register 2006 (December 15);71 (241): 75557-60.
DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.

Adverse-effects data: Natural Medicines, Therapeutic Research Center

Dosing

There is no well-established safe dose for cinchona bark as a supplement. The amount of quinine and other alkaloids can vary a lot from product to product, which makes safe dosing difficult.

If you are considering a cinchona product, follow the directions on the label and do not exceed them. Because of the real risk of serious side effects, it is best to talk with a pharmacist or doctor before taking it, especially if you take other medicines or have any health conditions.

Pregnancy & Breastfeeding

Cinchona & Pregnancy

Likely Unsafe

When used orally. Cinchona is reported to have uterine stimulant and abortifacient activity, and to be fetotoxic and teratogenic, causing visual and auditory defects. Avoid using.

  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

Cinchona & Breastfeeding

Possibly Unsafe

When used orally. The cinchona alkaloids quinine and quinidine are reported to be excreted in breast milk and may be toxic to infants.

  1. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.

© 2026 Therapeutic Research Center

Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center

References & further reading

The 15 references that drive our Cinchona monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  2. Wichtl MW. Herbal Drugs and Phytopharmaceuticals. Ed. N.M. Bisset. Stuttgart: Medpharm GmbH Scientific Publishers, 1994.
  3. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  4. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  5. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  6. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  7. Holt GA. Food & Possible Interactions with Drugs: Revised and Expanded Ed. Chicago, IL: Precept Press, 1998.
  8. Hardman JG, Limbird LL, Molinoff PB, eds. Goodman and Gillman's The Pharmacological Basis of Therapeutics, 9th ed. New York, NY: McGraw-Hill, 1996.
  9. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  10. Amabeoku GJ, Chikuni O, Akino C, Mutetwa S. Pharmacokinetic interaction of single doses of quinine and carbamazepine, phenobarbitone and phenytoin in healthy volunteers. East Afr Med J 1993;70:90-3.
  11. Shah BH, Nawaz Z, Virani SS, Ali IQ, Saeed SA, Gilani AH.The inhibitory effect of cinchonine on human platelet aggregation due to blockade of calcium influx. Biochem Pharmacol 1998;56:955-60. PubMed
  12. US Food and Drug Administration notice: Drug products containing quinine - enforcement action dates. Docket # 2006N-0476. Federal Register 2006 (December 15);71 (241): 75557-60.
  13. FDA Drug Safety Communication: New risk management plan and patient medication guide for Qualaquin (quinine sulfate). 07-08-2010. https://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/ucm218202 (accessed 02/18/17).
  14. Dooms-Goossens A, Deveylder H, Duron C, et al. Airborne contact urticaria due to cinchona. Contact Dermatitis 1986;15(4):258. PubMed
  15. Bramer SL, Suri A. Inhibition of CYP2D6 by quinidine and its effects on the metabolism of cilostazol. Clin Pharmacokinet. 1999;37 Suppl 2:41-51. PubMed
Keep reading

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.

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

Brand directory

Brands that make products with Cinchona

2 brands in our database make a supplement containing Cinchona.

Product directory

Supplement products with Cinchona

12 products in our database contain Cinchona. Open any to see its full ingredient list and every drug interaction we check.

Pharmacist Counseling Corner

Cinchona: Common Questions

What is Cinchona used for, and does it work?
People use Cinchona for a range of reasons, but according to the Natural Medicines database the current clinical evidence is insufficient to confirm it works for the specific conditions it has been studied for. See the graded list on this page, and talk to your pharmacist or doctor before relying on it for any condition.
Does Cinchona interact with prescription medications?
Yes. We list 492 medications with a known interaction with Cinchona, including 3 rated major. Use the checker above to see how Cinchona interacts with a specific drug.
How are Cinchona interactions rated?
Each interaction is graded major, moderate, or minor based on how clinically significant it is and the strength of the evidence behind it. Major interactions are the most serious and are best avoided, or used only under close professional supervision.
Is it safe to take Cinchona with my medications?
It depends on the specific medication. Some combinations are fine, while others call for monitoring, timing changes, or should be avoided. Check your exact drug above and confirm with your pharmacist or doctor before starting, stopping, or changing anything.
Where does this Cinchona interaction information come from?
Our interaction data is built on the Natural Medicines database — an evidence-graded reference for vitamins, herbs, and supplements — and is reviewed by licensed HelloPharmacist pharmacists, who may add clinical context.
What is Cinchona used for?
Cinchona bark is the natural source of quinine and has been used for centuries for malaria and fever. People also use it traditionally for leg cramps, restless legs, and digestive upset, but evidence for most of these uses is limited.
Is Cinchona the same as quinine?
Not exactly. Cinchona is the bark, and quinine is one of the active compounds inside it. The bark also contains other alkaloids, and the amount of quinine in bark products is not standardized.
Is Cinchona safe to take?
It can be risky. Cinchona contains quinine, which can cause ringing in the ears, low platelets, allergic reactions, and heart rhythm problems. Check with a pharmacist or doctor before using it.
Can I use Cinchona during pregnancy or breastfeeding?
No. Cinchona should be avoided during pregnancy and breastfeeding because quinine may not be safe for the baby and its safety in supplement form has not been established.

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

Keep exploring

Products that contain Cinchona

A rotating sample of real supplements in our database that list Cinchona — open any to see its full ingredients and every drug interaction we check.

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