Poison Ivy - Oak or Sumac

Symptoms

DEFINITION

  • Localized red rash with small blisters following poison ivy, oak or sumac exposure
  • Rash is very itchy
  • Located on exposed body surfaces (such as the hands) or areas touched by the hands (e.g., the face or genitals)

General Information

  • Poison Ivy, Poison Sumac, and Poison Oak are three plants that can cause an itchy red rash in sensitive individuals. The oil contained in the plant leaves irritates the skin. The redness and blistering from the rash is often arranged in streaks or lines, because the leaves brush across the body in a line as an individual walks past.
  • Onset:  Following a first-time exposure, the onset time for the rash is 1 to 2 weeks. For recurrences, the onset is 8 to 48 hours after the individual was in a forest or field.

Preventing the Rash!

  • Avoid Exposure: Avoid exposure to these plants, especially if you have had a bad reaction in the past.
  • Wash skin: If you are exposed, remove the irritating plant oil from your skin as soon as possible. Wash the exposed part of your body with soap and water within 30 minutes. Wash your clothes in warm soapy water.
  • IvyBlock: An over the counter cream that you put on your skin before walking in the woods. It coats the skin and acts as a barrier to the irritating oil of the poison ivy/oak/sumac plants and prevents the rash from occurring. More information is available at http://www.ivyblock.com.

Should I Call?

WHEN TO CALL YOUR DOCTOR

Call Your Doctor Now (night or day) If

  • You feel weak or very sick
  • Difficulty breathing or severe coughing following exposure to burning weeds
  • Fever and bright red area or streak (from open poison ivy sores)
  • Increasing redness around poison ivy and larger than 2 inches (5 cm)

Call Your Doctor Within 24 Hours (between 9 am and 4 pm) If

  • You think you need to be seen
  • Swelling is severe (e.g., the eyes are swollen shut)
  • Severe poison ivy reaction in the past
  • Severe itching interferes with normal activities (e.g., work or school) or prevents sleep
  • Rash involves more than one fourth of the body
  • Face, eyes, lips or genitals are involved
  • Big blisters or oozing sores
  • Taking oral steroids more than 24 hours and rash becoming worse

Call Your Doctor During Weekday Office Hours If

  • You have other questions or concerns
  • Rash lasts longer than 3 weeks

Self Care at Home If

  • Mild poison ivy, oak or sumac rash and you don't think you need to be seen

Care at Home

HOME CARE ADVICE FOR MILD RASH FROM POISON IVY, OAK OR SUMAC

  1. Hydrocortisone Cream for Itching:
    • Apply 1% hydrocortisone cream 4 times a day to reduce itching. Use it for 5 days.
    • Keep the cream in the refrigerator (Reason: it feels better if applied cold)
    • Available over-the-counter in U.S. as 0.5% and 1% cream.
    • Available over-the-counter in Canada as 0.5% cream.
  2. Local Cold: Soak the involved area in cool water for 20 minutes or massage it with an ice cube as often as necessary to reduce itching and oozing.
  3. Oral Antihistamine Medication for Itching: Take an antihistamine by mouth to reduce the itching. Diphenhydramine (Benadryl) is available over-the-counter. Adult dose is 25-50 mg. Take it up to 4 times a day.
    • Do not take antihistamine medications if you have prostate enlargement.
    • Antihistamines may cause sleepiness. Do not drink, drive or operate dangerous machinery while taking antihistamines.
    • An over-the-counter antihistamine that causes less sleepiness is loratadine (e.g., Alavert or Claritin).
    • Read the package instructions thoroughly on all medications that you take.
  4. Avoid Scratching: Cut your fingernails short and try not to scratch so as to prevent a secondary infection from bacteria.
  5. New Blisters Appear: If new blisters occur several days after the first ones, you probably have had ongoing contact with the irritating plant oil. To prevent recurrences: bathe all dogs and wash all clothes and shoes that were with you on the day of exposure.
  6. Contagiousness: Poison ivy or oak is not contagious to others.
  7. Expected Course: Usually lasts 2 weeks. Treatment reduces the severity of the symptoms, not how long they last.
  8. Call Your Doctor If:
    • Rash lasts longer than 3 weeks
    • It looks infected
    • You become worse

And remember, contact your doctor if you develop any of the "Call Your Doctor" symptoms.

Photo Example

 

Poison Ivy Plant (Example 1)

The leaves appear in groups of three.

Poison ivy grows as a small plant, as a bush, or as a vine.


Source: Wikimedia Commons

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License.

This is a public domain image file from Wikimedia Commons. Wikimedia is a freely licensed media repository.

 

Poison Ivy Rash on Forearm

The oil contained in the plant leaves irritates the skin.

The redness and blistering from the rash is often arranged in streaks or lines, because the leaf brushes across the body in a line as an individual walks past.

Source: LMS Inc.

Copyright 2000-2009. Self Care Decisions, LLC. Used by Permission.


 


Poison Ivy Rash on Wrist

Source: LMS Inc.

Copyright 2000-2009. Self Care Decisions, LLC. Used by Permission.

 

Poison Ivy Plant (Example 2)

Leaves grouped in threes characterize poison ivy. The scientific name for this plant is Toxicodendron radicans.

Poison Ivy is common in the eastern and central United States


Source: CDC PHIL

From the CDC's Public Health Image Library (http://phil.cdc.gov), ID#1110, in the public domain.

Content Providers: CDC / Dr. Edwin P. Ewing.

 

Poison Oak Plant

Source: Wikimedia Commons

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License.

This is a public domain image file from Wikimedia Commons. Wikimedia is a freely licensed media repository.

 

Poison Sumac Plant

Source: Wikimedia Commons

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License.

This is a public domain image file from Wikimedia Commons. Wikimedia is a freely licensed media repository.

Author and Senior Reviewer: David A. Thompson, M.D. Clinical content review provided by Senior Reviewer and Healthpoint Medical Network.

Last Review Date: 6/1/2011

Last Revised: 12/20/2009

Content Set: Adult HouseCalls Symptom Checker

Version Year: 2012

Portions Copyright 2000-2012 Self Care Decisions LLC; Copyright LMS, Inc.

Disclaimer: This information is not intended be a substitute for professional medical advice. It is provided for educational purposes only. You assume full responsibility for how you choose to use this information.

Instructions: The first purpose of Adult HouseCalls Symptom Checker is to help you determine how sick you are and if you need to call your doctor. The second purpose is to help you treat yourself at home when it is safe to do so. Your doctor's advice and your good judgment should always take precedence over information in these topics.

When to Call Your Doctor

Copyright 

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Are You Sick?

David A Thompson, MD is the author of Adult HouseCalls Symptom Checker. He is a board-certified emergency medicine physician at Northwestern Memorial Hospital in Chicago. He has a national reputation in telephone triage, decision support tools, medical information technology and quality improvement. Adult HouseCalls Symptom Checker is a decision support tool for adults that has been reviewed and approved by adult physicians.

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