Drug & supplement interaction

Arimistane + Colesevelam

Colesevelam brand names: WelChol, Lodalis.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Arimistane and Colesevelam in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first. Additionally, although there is no interaction, the label for Colesevelam states a food rule worth keeping to.

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Interaction report

Arimistane and Colesevelam

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Colesevelam and Arimistane in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Arimistane safety at a glance

Arimistane overall Avoid It is a hormone-altering drug with little safety data, and regulators warn against aromatase inhibitor supplements.
Pregnancy Possibly Unsafe When used orally or parenterally. The U.S. Food and Drug Administration and other regulatory agencies warn that dietary supplements containing aromatase inhibit... Read the full pregnancy detail
Breastfeeding Possibly Unsafe When used orally or parenterally. The U.S. Food and Drug Administration and other regulatory agencies warn that dietary supplements containing aromatase inhibit... Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Colesevelam and Arimistane? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Colesevelam

Interactions in our licensed database are recorded against drug classes, not just single drug names. Colesevelam is filed under a single classification — oral drugs. Arimistane has documented interactions with 1 drug class — the most serious being aromatase inhibitors (moderate) — and none of Colesevelam’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Arimistane Does Interact With Other Medications

Arimistane has 4 moderate known drug interactions in our database — Colesevelam isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Arimistane

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

What to actually watch for

What Colesevelam’s Own FDA Label Lists

This is not an interaction — none of it involves Arimistane. These are the most notable effects listed in the ADVERSE REACTIONS section of Colesevelam’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both. 10 of them are worth acting on rather than waiting out — marked below.

  • A bowel blockage Worth acting on
  • Trouble swallowing Worth acting on
  • Low blood sugar Worth acting on
  • A slow heartbeat Worth acting on
  • A heart attack Worth acting on
  • Pancreatitis Worth acting on
  • High blood sugar Worth acting on
  • Seizures Worth acting on
  • Raised blood pressure Worth acting on
  • A higher chance of infection Worth acting on

Showing the 10 most notable of 24 label-listed effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

From the ADVERSE REACTIONS section of the FDA label for Colesevelam. Read the label on DailyMed › Where a percentage is shown, it is the share of 2,014 voluntary FDA FAERS reports for Colesevelam that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. Arimistane’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Arimistane side to compare — that is a limit of the record, not a statement that Arimistane has no side effects.

Special populations

Arimistane in Pregnancy & Breastfeeding

Pregnancy And Lactation Possibly Unsafe

When used orally or parenterally. The U.S. Food and Drug Administration and other regulatory agencies warn that dietary supplements containing aromatase inhibitors are dangerous. 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

How to take them

Some Colesevelam Products Have a Food Rule — Arimistane Should Not Break It

At least one FDA label for a product containing Colesevelam says to take it with food. If you take Arimistane on an empty stomach out of habit, keep them separate — and take Colesevelam with a meal where the label says to.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Colesevelam products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

Colesevelam hydrochloride should be taken as follows ( 2.2 , 2.4 ): Tablets Take 6 tablets once daily or 3 tablets twice daily with a meal and liquid.

From the Dosage and Administration section of the FDA label we read for Colesevelam — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

From our Q&A

Questions About Arimistane or Colesevelam

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Arimistane or Colesevelam, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Colesevelam

This page covers Arimistane only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Colesevelam page lists 17 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Glucomannan (moderate) and Guar Gum (moderate).

By severity: 1 major · 7 moderate · 9 minor.

From our pharmacist’s overview on the Colesevelam page

“Colesevelam (WelChol, Lodalis) lowers cholesterol by binding bile acids in your gut, and every one of the 17 supplements on this list can interfere with how oral medicines are absorbed in that same territory. I would treat this list with genuine care, and the place to start is activated charcoal, the only major-rated entry.”

Reviewed by 2 · Jul 18, 2026

Open the Colesevelam interaction page

One more smart check

Taking Arimistane as Part of a Dietary Supplement Product? Check It for Interactions

We hold 80 real supplement products containing Arimistane, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Arimistane. Even though Arimistane itself has no known interaction with Colesevelam, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Arimistane and Colesevelam 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 Arimistane
Top half

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

29 days ago today
Medication Colesevelam
Steady interest

#2,234 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Arimistane reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Arimistane and Colesevelam records this page draws on were last updated June 22, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Arimistane

What is Arimistane?

Arimistane
  • Lowering estrogen levels
  • Post-cycle therapy after steroid or prohormone use
  • Reducing gynecomastia ('gyno')
  • Boosting testosterone
  • Bodybuilding and physique support

Arimistane (sometimes sold as Estrovade) is a synthetic aromatase inhibitor marketed as a dietary supplement to lower estrogen and raise testosterone, often during or after steroid or prohormone cycles. It is not a true dietary ingredient, has very little human safety data, and U.S. regulators have warned against products containing aromatase inhibitors. Talk to a pharmacist or doctor before using it.

Not applicable (synthetic compound) · Capsules, tablets, powders

An interaction check asks whether these two react with each other — it does not ask whether Arimistane is a good idea for someone in your situation. Here is what our Arimistane record says about it on its own.

Arimistane: dosing

There is no officially established or proven safe dose for Arimistane. It has not gone through the testing that approved medicines undergo, so reliable dosing guidance does not exist.Product labels vary widely, and the actual amount in a given product may not match what is claimed. Honestly, for most people the safest choice is to avoid it.

From our Arimistane monograph — the full record covers uses, side effects and every documented interaction.

Read the full Arimistane monograph & all interactions
Medication

About Colesevelam

What Is Colesevelam Used For?

Brand names: WelChol, Lodalis

Colesevelam is used alongside diet and exercise to reduce high LDL cholesterol (the "bad" cholesterol) in adults with primary hyperlipidemia (high cholesterol). It is also approved to lower LDL cholesterol in boys and girls aged 10–17 who have heterozygous familial hypercholesterolemia (HeFH) — an inherited condition that causes very high cholesterol — when diet and lifestyle changes alone haven't worked.

Colesevelam tablets and oral suspension (Welchol and colesevelam hydrochloride products) are also used to improve blood sugar control in adults with type 2 diabetes, as an add-on to diet and exercise. Colesevelam is not for type 1 diabetes or diabetic ketoacidosis.

Most-Reported Side Effects for Colesevelam

From FAERS, the FDA’s public side-effect reporting system (2,014 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Diarrhea 241 reports
Dyspnea 172 reports
Cough 169 reports
Muscle spasms 163 reports
Nasopharyngitis 150 reports
See full Colesevelam drug information
Keep checking

Other Drugs & Arimistane

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

0Major
4Moderate
0Minor
2,825No known interaction
Moderate

4 interactions

No interaction 2,825 drugs checked — show the list
Evidence & sources

Arimistane References

The 1 references that drive our Arimistane 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. Joseph JF, Parr MK. Synthetic androgens as designer supplements. Curr Neuropharmacol. 2015;13(1):89-100. PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Arimistane and Colesevelam Together: Common Questions

Is it safe to take Arimistane with Colesevelam?
We do not list a known interaction between Arimistane and Colesevelam. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
Should I take Arimistane and Colesevelam at the same time of day?
At least one FDA label for a product containing Colesevelam says to take it with food. If you take Arimistane on an empty stomach out of habit, keep them separate and take Colesevelam with a meal where the label says to. Food instructions belong to the product rather than the ingredient — two Colesevelam products can differ — so check the directions on your own box. This is about absorption, not an interaction.
How was the Arimistane and Colesevelam combination checked?
Interactions in our licensed database are recorded against drug classes. Colesevelam is filed under 1 classification, and Arimistane has documented interactions with 1 drug class — none of Colesevelam's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Arimistane interact with any other medications?
Yes. Arimistane has 4 documented drug interactions in our database — Colesevelam is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Colesevelam interact with any supplements?
Yes. Colesevelam has documented interactions with 17 supplements in our database — Arimistane is not one of them. The Colesevelam interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Colesevelam and Arimistane?

Our pharmacists answer your medication & supplement questions — free.

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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.