Emodin

PhytochemicalAnthraquinone

What is it

Emodin is an anthraquinone compound found in rhubarb (Rheum), buckthorn (Frangula, Rhamnus), Polygonum cuspidatum (Japanese knotweed), and aloe. It contributes to the stimulant laxative effects of these plants and has been studied for various pharmacological effects.

Evidence for 2 uses

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

Constipation (as anthraquinone laxative)

Good Evidence

Anthraquinone laxatives are effective for short-term constipation relief.

Antiviral and antitumor (research)

Mixed Evidence

Preclinical activity reported. Human evidence absent.

How it works

As an anthraquinone, emodin (after activation by colonic bacteria) acts as a stimulant laxative by inducing colonic smooth-muscle contraction and reducing water absorption. Beyond its laxative effect, emodin has shown in preclinical studies anti-inflammatory, antiviral, antibacterial, antitumor, and PPAR-gamma modulating activity, with some interest in its potential anti-SARS-CoV-2 activity. Emodin is also genotoxic in some assays, raising concerns about long-term high-dose use.

Dosage

No specific human supplement dose. Daily anthraquinone laxative doses (from various plants) provide emodin in the milligram range; concentrated emodin supplements are not common.

When and how to take it

Laxative effect typically occurs 8 to 12 hours after ingestion. Not for chronic use.

2 commercial forms

Compare the main delivery options and what they’re best suited for.

Emodin (research)

Mostly a research compound; not commonly sold as a standalone supplement.

Limited absorption; variable bioavailability.

Emodin-containing plants (Rheum, aloe latex)

Source of emodin in traditional and OTC laxative products.

Activated by colonic bacteria.

Safety

Chronic anthraquinone laxative use can cause melanosis coli, electrolyte loss, and dependence. Emodin is genotoxic in some in vitro tests and has raised concerns in safety reviews of products containing high levels (e.g., aloe latex products).

Who should be cautious

Avoid in pregnancy (anthraquinones can stimulate uterine contractions), breastfeeding (passes into milk and can cause infant diarrhea), and chronic kidney or liver disease. Avoid in children.

Interactions

May reduce absorption of medications taken concurrently. Potassium loss from laxative effects can potentiate digoxin and interact with diuretics.

Frequently asked questions

Is emodin safe?⌄

Short-term use as part of laxative products is generally tolerated. Long-term or high-dose use raises safety concerns due to genotoxicity signals.

Does emodin treat cancer?⌄

Preclinical activity has been reported but no human evidence supports its use as a cancer treatment.

References

Emodin on Wikidata — Wikidata link

Emodin (ChEBI:42223) — ChEBI link

Emodin (PubChem CID 3220) — PubChem link

Emodin on NIH DSLD (US supplement label database) — NIH Dietary Supplement Label Database link

Research on Emodin (PubMed search) — PubMed link

Track Emodin with Pilora

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Evidence-based·How we grade evidence

Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.