First Aid for Poison Ivy
Advice on avoiding and treating reactions from exposures to poison ivy, poison oak and poison sumac, which are the most common plants that cause a skin rash.
http://www.healthy.net/library/BOOKS/HEALTHYSELF/FIRSTAID/poisonivy.htm

Poison Ivy: an Exaggerated Immune Response to Nothing Much
Brief technical article on allergic reactions to poison ivy, including physiology, treatment options and links to related information.
http://www.bio.umass.edu/immunology/poisoniv.htm

Go Ask Alice!: Poison Ivy, Oak and Sumac
Advice on symptoms and treatment, including when to seek emergency medical care. From Columbia University Health Education Program.
http://www.goaskalice.columbia.edu/1354.html

RXinsider
Short informational monograph on poison ivy/oak/sumac and their treatment.
http://rxinsider.com/monographs/poison_oak_and_ivy.htm

Dr. Greene - Poison Ivy, Poison Oak or Poison Sumac
Advice in a question and answer format.
http://www.drgreene.org/body.cfm?id=21&action=detail&ref=116

Poison Ivy Tutorial
Pictures, reference, and quiz on poison ivy's identification, rash, treatment, and the urushiol oleoresin.
http://www.cattail.nu/ivy/

Allergy: Poison Ivy, Oak, and Sumac
Consumer health resource center providing and overview of the key identifiers, symptoms, and treatments of three topical plant allergies. From eMedicine Health.
http://www.emedicinehealth.com/articles/8435-1.asp

Survive Outdoors Inc.
Detailed pictures of poison ivy rashes and lookalikes.
http://www.surviveoutdoors.com/emergency/poisonivy.asp

MedicineNet: Poison Ivy, Oak & Sumac
Includes causes, who is susceptible, treatment if exposed, and prevention.
http://www.medicinenet.com/poison_ivy/article.htm

Outsmarting Poison Ivy and Its Cousins
US FDA advice on prevention and control of reactions, including common treatments.
http://www.fda.gov/fdac/features/796_ivy.html

Poison Oak FAQ
General information, its history, treatments, etiquette rules, and anecdotes.
http://knoledge.org/oak/