Drug & supplement interaction

Padang Cassia + Exemestane

Exemestane brand name: Aromasin.

Moderate Interaction
The bottom line Moderate

Padang Cassia has a moderate interaction with Exemestane. In vitro research shows that a methanol extract of Padang cassia inhibits cytochrome P450 3A4 (CYP3A4) activity.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Padang Cassia and Exemestane

Here is the interaction we found between these two, with the evidence behind it.

Moderate

CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES

Why this applies to Exemestane

Exemestane falls under CYTOCHROME P450 3A4 (CYP3A4) SUBSTRATES — the group Padang Cassia interacts with.

In vitro research shows that a methanol extract of Padang cassia inhibits cytochrome P450 3A4 (CYP3A4) activity. Theoretically, taking Padang cassia with CYP3A4 substrates might increase the effects and side effects of these substrates.
Severity Moderate Likelihood Possible Evidence D

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.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the situation with Exemestane (Aromasin) and concentrated cinnamon supplements. Your liver uses an enzyme called CYP3A4 to help process exemestane. In a test-tube study, an extract of Padang cassia slowed this enzyme down a bit. In theory, if that enzyme works more slowly, your body could clear exemestane a little less efficiently, leaving slightly more in your system and possibly nudging up side effects like hot flashes, joint or muscle aches, fatigue, or headaches.

I want to keep this in perspective. This is based only on lab research, not real patients, so the actual risk is uncertain and likely small. Sprinkling cinnamon on your food is no concern. If you're thinking about a daily cinnamon capsule, please run it by your oncologist or pharmacist first.

References
  1. Subehan S, Kadota S, Tezuka Y. In vitro mechanism-based inactivation of cytochrome P450 3A4 by a new constituent of Cinnamomum burmani. Planta Med 2008;74(12):1474-80.

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • 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.
Evidence the quality of the studies behind the rating (graded A–D)
  • 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.

Keep it in perspective

Padang Cassia Also Interacts With Other Medications

Padang Cassia has 933 moderate known drug interactions in our database — the Exemestane one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Padang Cassia

Covers the 2,830 medications we’ve checked against Padang Cassia. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Exemestane

This page covers Padang Cassia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Exemestane page lists 141 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), St. John's Wort (major), 7-methoxyflavone (moderate) and Acacia Rigidula (moderate).

By severity: 3 major · 98 moderate · 40 minor.

From our pharmacist’s overview on the Exemestane page

“Exemestane (Aromasin) is an aromatase inhibitor for hormone-sensitive breast cancer, and because its job is keeping estrogen suppressed, anything that shifts its blood level puts the treatment itself at risk. This list deserves real care.”

Reviewed by 2 · Jul 18, 2026

Open the Exemestane interaction page

How much people look this up

Where Padang Cassia and Exemestane 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.

Supplement Padang Cassia
Steady interest

#851 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Exemestane
Steady interest

#1,699 of 2,830 medications looked up here in the last 7 days

29 days ago today

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.

Supplement

About Padang Cassia

What is Padang Cassia?

  • Adding flavor to food
  • Digestive upset
  • Blood sugar support
  • Antimicrobial purposes
  • Antioxidant support

Padang Cassia is a type of cinnamon (Indonesian or Korintje cinnamon) grown mainly in Indonesia and used widely as a kitchen spice. As a supplement, evidence for health benefits like blood sugar control is limited and mixed, and like other cassia cinnamons it naturally contains coumarin, which can be harmful to the liver in large amounts. Use food amounts freely, but talk to a pharmacist or doctor before taking concentrated cinnamon supplements.

Read the full Padang Cassia monograph & all interactions
Medication

About Exemestane

What Is Exemestane Used For?

Brand name: Aromasin

Exemestane (brand name Aromasin) is used in postmenopausal women with estrogen-receptor positive early breast cancer who have already taken tamoxifen for two to three years — it is then used to complete a total of five years of hormonal therapy. It is also used to treat advanced breast cancer in postmenopausal women whose cancer continued to grow during or after tamoxifen therapy.

These uses apply to Aromasin and the generic exemestane tablets. This medication is not approved for breast cancer in premenopausal women.

See full Exemestane drug information
Keep checking

Other Drugs & Padang Cassia

Browse every other medication we’ve checked against Padang Cassia — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
933Moderate
0Minor
1,896No known interaction
Moderate

933 interactions

Showing 60 of 933 moderate interactions — see all 933 on the Padang Cassia page.

No interaction 1,896 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

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

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Pharmacist Counseling Corner

Taking Padang Cassia and Exemestane Together: Common Questions

Can you take Padang Cassia with Exemestane?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Padang Cassia and Exemestane interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Exemestane and Padang Cassia?

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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.