Limited evidenceGut health

Black Walnut Hull

A traditional parasite-cleanse ingredient, usually paired with wormwood and clove. There is no human trial of any kind; the published work is laboratory and veterinary, and mostly on the English walnut rather than the black.

Evidence last reviewed: August 2026

What the science says

Antiparasitic use Limited evidence
The closest evidence is a veterinary study in which an ethanolic Juglans regia leaf extract killed the poultry roundworm Ascaridia galli in vitro and in birds. Nothing has been tested in humans, and black walnut hull specifically has not been studied.
Antimicrobial activity Limited evidence
An in vitro study of green walnut hull from Juglans regia reported antibacterial and free-radical scavenging activity. Activity in a dish does not predict what happens in the human gut.

Dosage & safety

Studied doseNo studied dose exists. Tinctures are typically labelled at 0.5–2 mL up to three times daily and capsules at around 500 mg, figures drawn from tradition.

SafetyJuglone-containing hulls stain skin and can irritate the gut; prolonged use is not advisable. Avoid entirely with tree-nut allergy, and in pregnancy and breastfeeding. Suspected parasitic infection should be confirmed by stool testing and treated with proven drugs.

Scientific references

Evaluation of anthelmintic efficacy of ethanolic leaf extract of Juglans regia L. on Ascaridia galli: a comprehensive in vitro and in vivo study
Mir FH, Tanveer S, Para BA — Vet Res Commun, 2024
In vitro antibacterial and free radical scavenging activity of green hull of Juglans regia
Sharma P, Ravikumar G, Kalaiselvi M — J Pharm Anal, 2013

Where to buy

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