Herb & supplement monograph

Aspen Drug Interactions, Uses, Safety & More

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

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

But these pages have grown well beyond that into a full monograph — what Aspen 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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Aspen 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 Aspen drug interaction appears low for most people, since every listed concern is theoretical rather than proven. None of the interactions are rated major, and all of them rest on lab-based reasoning about aspen's chemistry rather than studies in people.

Interactions deserving the most attention

The interactions that deserve the most attention involve aspirin and other salicylate medications, such as salsalate and choline magnesium trisalicylate. Aspen contains salicin, a natural plant salicylate, so combining it with these drugs could in theory add to their effects in the body. This possibility has not been confirmed in human studies, but it is a reasonable point of caution for anyone who takes a salicylate regularly.

What the rest of the list means

Although aspen is linked to a fairly long list of medications, essentially all of them trace back to this single salicylate concern. A long list does not mean every combination is harmful, and none of these predicted effects has been shown to cause meaningful problems in people. The concern is a prediction based on what aspen contains, not on documented harm.

Check your medications against Aspen

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

Interaction report

Drugs that interact with Aspen

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

2,830 drugs
Acetaminophen, AspirinGemnisyn› Acetaminophen, Aspirin, CaffeineExcedrin, Excedrin Extra Strength, Excedrin Migraine› Acetylsalicylic AcidEntrophen› Aluminum Hydroxide, Aspirin, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #2› Aluminum Hydroxide, Aspirin, Magnesium HydroxideAscriptin› AspirinAngettes 75, ASA, Asaphen, Aspirin, Caprin, Cartia +8 more› Aspirin, Aluminum Hydroxide, Codeine Phosphate, Magnesium HydroxideAscriptin Codeine #3› Aspirin, ButalbitalAxotal› Aspirin, Butalbital, CaffeineFiorinal› Aspirin, Butalbital, Caffeine, Codeine PhosphateFiorinal w/ Codeine› Aspirin, Butalbital, Caffeine, PhenacetinMarnal› Aspirin, CaffeineAnacin› Aspirin, Caffeine, Codeine PhosphateAnacin w/ Codeine› Aspirin, Caffeine, Dihydrocodeine BitartrateSynalgos DC› Aspirin, Caffeine, Dover's PwdAcedoval, Dovacet› Aspirin, Caffeine, HydrocodoneDamason-P› Aspirin, Caffeine, Isobutylallylbarbituric Acid, PhenacetinLanorinal› Aspirin, Caffeine, OrphenadrineInvagesic, Invagesic Forte, Norgesic, Norgesic Forte, Orphengesic, Orphengesic Forte› Aspirin, Caffeine, Phenacetin, PropoxypheneMargesic Comp. 65› Aspirin, Calcium Carbonate, Magnesium Carbonate, Magnesium OxideBufferin› Aspirin, CarisoprodolSoma Compound› Aspirin, Carisoprodol, Codeine PhosphateSoma Compound w/ Codeine› Aspirin, Chlorpheniramine, PhenylpropanolamineAlka-Seltzer Plus Cold› Aspirin, Citric Acid, Sodium BicarbonateAlka-Seltzer Pain Reliever and Antacid› Aspirin, Codeine PhosphateAspirin w/ Codeine› Aspirin, Codeine Phosphate, MethocarbamolRobaxisal C› Aspirin, Codeine Phosphate, PhenobarbitalPhenaphen› Aspirin, Diphenhydramine, PhenylpropanolamineAlka Seltzer Plus Night Time Effervescent› Aspirin, DipyridamoleAggrenox, Asasantin Retard› Aspirin, Ethoheptazine, MeprobamateEquagesic›
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 Aspen 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 Aspen affects

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

All 3 drug categories Aspen interacts with
AspirinCholine Magnesium Trisalicylate (trilisate)Salsalate (disalcid)
Aspirin

Aspen contains salicin, a plant salicylate. Theoretically, aspen might have an additive effect with other salicylate-containing drugs, such as aspirin.

Likelihood Possible Evidence D
Choline Magnesium Trisalicylate (Trilisate)

Aspen contains salicin, a plant salicylate. Theoretically, aspen might have an additive effect with other salicylate-containing drugs such as choline magnesium trisalicylate.

Likelihood Possible Evidence D
Salsalate (Disalcid)

Aspen contains salicin, a plant salicylate. Theoretically, aspen might have an additive effect with other salicylate-containing drugs such as salsalate.

Likelihood Possible Evidence D
Monograph

Aspen: Uses, Safety & Side Effects

Medically reviewed by · Reviewed July 2026 ·
The bottom line

Aspen bark and leaf contain salicin, a natural compound related to aspirin, which is why it is traditionally used for pain, fever, and inflammation. Solid human studies are lacking, and because it acts like aspirin it carries similar risks. Talk to your pharmacist or doctor before using it, especially if you are sensitive to aspirin.

Aspen
Scientific name
Populus tremuloides
Family
Salicaceae
Part used
Bark and leaves (sometimes leaf buds)
Common forms
Capsules, tinctures, liquid extracts, teas, and dried bark; often combined with other herbs
People commonly use it for
  • Joint and muscle pain
  • Arthritis-related discomfort
  • Urinary tract symptoms and prostate issues
  • Mild fever and inflammation
  • Nerve pain (sciatica, neuropathic pain)

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

Safety at a glance
OverallUse caution

It contains aspirin-like salicylates and may cause similar side effects, so use carefully.

PregnancyInsufficient reliable information

Insufficient reliable information available; avoid using.

Read the full pregnancy detail
BreastfeedingInsufficient reliable information

Insufficient reliable information available; avoid using.

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.

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Overview

Aspen is a tall deciduous tree found across cool, temperate parts of North America, Europe, and Asia. The two species most often used are Populus tremuloides (quaking or American aspen) and Populus tremula (European aspen). Its leaves flutter easily in the wind, which is why it is also called "trembling" or "quaking" aspen.

The bark and leaves are the parts used in herbal products. They contain salicin, a natural compound that the body can turn into a substance similar to the active part of aspirin. Because of this, aspen has a long history of folk use for pain, fever, and inflammation.

Today aspen is sold as capsules, tinctures, teas, and liquid extracts. It is often combined with other herbs such as goldenrod or ash bark in joint and urinary blends rather than used on its own.

Uses & effectiveness

People most commonly use aspen for joint and muscle pain, arthritis, fever, urinary tract symptoms, prostate complaints, and nerve pain. These uses come mainly from tradition and from the fact that aspen contains aspirin-like salicylates.

The human evidence is limited. Most research has looked at multi-herb products that include aspen, not aspen by itself, so it is hard to know how much benefit comes from the aspen. Some small studies of combination products suggest possible anti-inflammatory effects, but these are not strong enough to prove that aspen works for any specific condition.

Much of the supporting information comes from laboratory and animal studies rather than well-designed human trials. At this time there is not enough reliable evidence to say aspen is an effective treatment for arthritis, urinary infections, prostate problems, or nerve pain.

How it works

The best-known active compound in aspen is salicin, a plant salicylate. After it is absorbed, the body converts salicin into salicylic acid, which is chemically related to the active form of aspirin. This may help reduce pain, fever, and inflammation in a similar way.

Aspen also contains other plant compounds such as flavonoids and tannins, which have shown antioxidant and anti-inflammatory activity in laboratory tests. It is not clear how meaningful these effects are at the doses people actually take.

It is important to remember that most of these mechanisms are based on test-tube and animal research. They suggest how aspen might work but do not prove it provides these benefits in people.

Safety & precautions

Because aspen acts like aspirin, people who should avoid or be careful with aspirin should also be careful with aspen. This includes anyone with a known aspirin or salicylate allergy, a history of stomach ulcers or bleeding problems, asthma that worsens with aspirin, or kidney problems.

Children and teenagers with viral illnesses (such as flu or chickenpox) should not take aspen, since salicylates have been linked to a rare but serious condition called Reye's syndrome.

Stop using aspen and tell your surgeon or dentist if you have a procedure coming up, since salicylates can affect bleeding. During pregnancy and breastfeeding, aspen is best avoided because of its aspirin-like activity and the lack of safety information. Always check with your pharmacist or doctor before starting aspen, especially if you take other medicines or have a health condition.

Side effects

Because aspen contains salicylates, it may cause side effects similar to aspirin. These can include stomach upset, heartburn, nausea, and an increased risk of stomach irritation or bleeding.

Less commonly, people may have allergic reactions such as rash, itching, or trouble breathing—this is more likely in those sensitive to aspirin. Ringing in the ears can occur with high doses of salicylates.

Serious side effects are uncommon at normal amounts but can include stomach bleeding or severe allergic reactions. Stop taking aspen and seek medical care if you notice black or bloody stools, vomiting blood, severe stomach pain, or signs of an allergic reaction.

Aspen: Reported Adverse Effects

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

There is currently a limited amount of information available about the adverse effects of aspen. Aspen contains salicin, a plant salicylate. Theoretically, aspen taken orally may be associated with the adverse effects seen with other salicylates, such as aspirin. Topically, aspen has been associated with allergic dermatitis.

  1. Goodman LS, Gilman A. The Pharmacological Basis of Therapeutics. 5th ed. New York, NY: Macmillan Publ. Co., Inc., 1975.
  2. Aalto-Korte K, Välimaa J, Henriks-Eckerman ML, Jolanki R. Allergic contact dermatitis from salicyl alcohol and salicylaldehyde in aspen bark (Populus tremula). Contact Dermatitis 2005;52(2):93-5.
Reports by condition
Dermatitis Dermatologic

A case report describes a 58-year-old man who developed allergic contact dermatitis after handling aspen leaves and bark. The rash spread from his hands to his face, trunk, and extremities. He had positive skin patch tests to salicyl alcohol and salicylaldehyde, which are present in aspen as glucosides, such as salicin.

  1. Aalto-Korte K, Välimaa J, Henriks-Eckerman ML, Jolanki R. Allergic contact dermatitis from salicyl alcohol and salicylaldehyde in aspen bark (Populus tremula). Contact Dermatitis 2005;52(2):93-5.
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, standardized dose for aspen. The amount of salicin in products can vary widely, and many products combine aspen with other herbs.

The safest approach is to follow the directions on the specific product label and not exceed the recommended amount. Because aspen behaves like aspirin, do not combine it with other salicylate-containing products without professional advice.

Before starting aspen, talk with your pharmacist or doctor so they can help you decide whether it is appropriate and what amount, if any, is reasonable for you.

Pregnancy & Breastfeeding

Aspen & Pregnancy

Insufficient reliable information

Insufficient reliable information available; avoid using.

Aspen & Breastfeeding

Insufficient reliable information

Insufficient reliable information available; avoid using.

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 3 references that drive our Aspen 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. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  2. Goodman LS, Gilman A. The Pharmacological Basis of Therapeutics. 5th ed. New York, NY: Macmillan Publ. Co., Inc., 1975.
  3. Aalto-Korte K, Välimaa J, Henriks-Eckerman ML, Jolanki R. Allergic contact dermatitis from salicyl alcohol and salicylaldehyde in aspen bark (Populus tremula). Contact Dermatitis 2005;52(2):93-5.
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 Aspen

6 brands in our database make a supplement containing Aspen.

Product directory

Supplement products with Aspen

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

Pharmacist Counseling Corner

Aspen: Common Questions

Does Aspen interact with prescription medications?
Yes. We list 39 medications with a known interaction with Aspen. Use the checker above to see how Aspen interacts with a specific drug.
How are Aspen 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 Aspen 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 Aspen 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 Aspen used for?
People traditionally use Aspen bark and leaf for joint and muscle pain, arthritis, fever, urinary and prostate symptoms, and nerve pain. Strong human evidence supporting these uses is lacking.
Is Aspen the same as aspirin?
Not exactly, but Aspen contains salicin, a natural compound the body turns into a substance similar to aspirin's active form. This means it can have similar effects and similar risks.
Can I take Aspen if I'm allergic to aspirin?
No. If you are allergic or sensitive to aspirin or other salicylates, you should avoid Aspen because it may cause the same kind of reaction.
Is Aspen safe during pregnancy or breastfeeding?
It is best to avoid Aspen while pregnant or breastfeeding. There is not enough safety information, and its aspirin-like compounds may not be safe for the baby.

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

Keep exploring

Products that contain Aspen

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

See all 8 products with Aspen →
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