How to describe rash of poison ivy?
If you develop black spots or streaks, there tends to be little or no redness and swelling. The medical term for this condition is black-spot poison-ivy dermatitis.
It takes time for the rash to appear. A rash can develop in a few hours if you’ve had a rash from one of these plants before. If you’ve never had a rash from poison ivy, oak, or sumac, it can take 2 to 3 weeks before you see a rash.
No matter how long it takes for the rash to appear, most people experience the following when they get a rash:
The intensity of the itch and severity of the rash can differ from person to person. Some people develop 1 or 2 small rashes. Others develop rashes all over.
While it may look like the rash is spreading, what’s most likely happening is that you’re developing one or more new rashes. This happens because you either:
If your new rash appears near the current rash, it can look like the rash is spreading.
Many people also mistakenly believe that when they touch their rash, they can spread the rash from one part of their body to another. You cannot spread the rash.
If you have oil from the plant on your skin, you can spread the oil for a short time. Your skin absorbs the oil quickly, so you can only spread the oil from one part of your skin to another for a short amount of time.
How long you have a rash depends on whether you’ve had a rash from one of these plants before. Here’s the general rule:
If you’re wondering why you develop a rash from these plants, you’ll find the answer at: Poison ivy, oak, and sumac: Who gets a rash, and is it contagious?
Images Image 1 used with permission of the American Academy of Dermatology National Library of Dermatologic Teaching Slides.
Images 2,3 used with permission of the Journal of the American Academy of Dermatology.
Extreme itching. Red, streaky, patchy rash where the plant touched the skin. Red bumps, which may form large, weeping blisters.
You can treat the rash at home if you:
To treat a mild rash and help stop the itch, dermatologists recommend the following:
To treat the rash
What can relieve the itch?
If your rash is not improving after 7 to 10 days, or you think your rash may be infected, see a board-certified dermatologist. A dermatologist can treat your rash and any infection and help relieve the itch.
Dermatologists emphasize that you only treat the rash if you’re absolutely certain that poison ivy, oak, or sumac caused it. If you’ve never had a poison ivy rash, see a doctor for a diagnosis.
You’ll find pictures of what the rash can look like at: Poison ivy, oak, or sumac: What does the rash looks like?
Poison ivy is a common poisonous plant that causes an itchy skin rash. Other rash-inducing poisonous plants include poison oak and poison sumac. These plants produce an oily sap that contains urushiol (pronounced yer-OO-shee-all), which causes an irritating, itchy allergic reaction. When you touch the poisonous plant or an object that’s been in contact with the plant’s oil, you develop an itchy rash on that area of your skin. This rash is a form of allergic contact dermatitis.
Up to 90% of people who come into contact with poison ivy oil develop an itchy rash. You don’t have to be exposed to much: 50 micrograms (μg) of urushiol — an amount smaller than a grain of salt — is enough to cause a reaction. You can become susceptible to a poison ivy rash at any time in your life, even if you never reacted to it in the past.
Nearly everyone who touches urushiol gets a poison ivy rash. You’re more likely to come into contact with a poisonous plant if you’re a:
Poisonous plants grow everywhere in the United States except Hawaii and Alaska. Each type has a distinctive appearance.
If you’re wondering how to identify poison ivy, look at its leaves. Each leaf of the poison ivy plant has three leaflets. A popular saying is, “leaves of three, let them be.” Poison ivy leaves turn reddish in the spring, green in the summer and yellow, orange or red in the fall.
Poison ivy grows as a shrub or a vine. A poison ivy vine is hairy and ropelike. Eastern U.S. poison ivy typically grows as a vine. Western U.S. poison ivy normally grows low to the ground as a shrub. Poison ivy does not have thorns. A poison ivy shrub may have white berries.
Poison oak leaves have three leaflets like poison ivy but with rounded tips. The undersides of the leaves are fuzzy and lighter in color than the top.
