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Poison ivy, oak, and sumac

Last reviewed: 9 Apr 2025
Last updated: 18 Nov 2022

Summary

Definition

History and exam

Key diagnostic factors

  • pruritus
  • blisters and vesicles
  • weeping, oozing, and crusting
Full details

Other diagnostic factors

  • previous exposure
  • breathing difficulties
  • generalized erythroderma
  • periorbital edema
  • systemic contact dermatitis
  • black-spot dermatitis
Full details

Risk factors

  • occupation that involves exposure to relevant trees and plants
  • outdoor activities
  • domestic pets and livestock
  • use of forestry equipment and machinery
  • smoke from burning Toxicodendron species
  • children
  • genetic susceptibility
Full details

Diagnostic tests

1st tests to order

  • clinical diagnosis
Full details

Tests to consider

  • botanical identification
  • black-spot test
Full details

Emerging tests

  • patch test

Treatment algorithm

INITIAL

immediate treatment postexposure

ACUTE

mild dermatitis

moderate dermatitis

severe dermatitis

ONGOING

chronic severe dermatitis from repeated exposure

Contributors

Authors

Marius Rademaker, BM FRCP, FRACP DM, FNZDSI

Honorary Associate Professor of Dermatology

Waikato Clinical Campus

University of Auckland

Hamilton

New Zealand

Disclosures

MR declares that he has no competing interests.

Peer reviewers

Brian Swick, MD

Clinical Assistant Professor

University of Iowa College of Medicine

Iowa City

IA

Disclosures

BS declares that he has no competing interests.

Christopher Lovell, MBBS

Consultant Dermatologist

Kinghorn Dermatology Unit

Royal United Hospital

Bath

UK

Disclosures

CL declares that he has no competing interests.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

Guin JD, Beaman JH, Baer H. Toxic anacardiaceae. In: Avalos J, Maibach HI, eds. Dermatologic botany. Boca Raton, FL: CRC Press; 1999.

Rozas-Muñoz E, Lepoittevin JP, Pujol RM, et al. Allergic contact dermatitis to plants: understanding the chemistry will help our diagnostic approach. Actas Dermosifiliogr. 2012 Jul-Aug;103(6):456-77.Full text  Abstract

Guin JD, Beaman JH. Toxicodendrons of the United States. Clin Dermatol. 1986 Apr-Jun;4(2):137-48. Abstract

Paniagua CT, Bean AS. Black-spot poison ivy: a rare phenomenon. J Am Acad Nurse Pract. 2011 Jun;23(6):275-7. Abstract

Reference articles

A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

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