Recently a patient came to our dermatology clinic with a rash and a history similar to many others. He’d camped with friends a few days ago and helped carry some logs to start the fire.
Little did he know that he would pay to help him. A few days later, red spots appeared on his forearms and chest, which soon began to itch and form water blisters.
If you’ve spent any time outdoors – in the woods, gardening, even on the edge of a playground – you may have experienced something similar after encountering poison ivy. It is not easy to forget.
Poison ivy: where to find it
Poison ivy is found throughout the continental US, mainly in the Eastern and Midwestern states. Unfortunately for us humans, it is a tough plant that can grow in many different conditions. His favorite places are in wooded areas, gardens and roadsides with partial shade or full sun.
And while it’s a nuisance to humans, poison ivy is an important member of the ecosystem. Its leaves, stems, and berries are food for animals, and its tendrils can shelter small animals such as toads and mice, and even help them climb trees. Climate change benefits poison ivy and allows for larger and more irritating plants.
You can usually recognize poison ivy by its infamous three dull or glossy green leaves that come off a red stem. Sometimes flowers or fruit come from the end of a branch.
Despite its name, poison ivy is not poisonous. It carries an oily juice called urushiol on its leaves and stems, which is irritating to most people’s skin. In fact, 85 to 90 percent of people are allergic to the urushiol from poison ivy to some degree, while the rest are not sensitive to this oil.
You can occasionally see the urushiol oil as black spots on the leaves of the poison ivy. Urushiol also gives poison oak and poison sumac their evil power.
Touching poison ivy directly is obviously a bad idea. You can even get into trouble by touching clothing, pets, or anything else that has brushed against the plant and ingested some of the urushiole.
If a contaminated item isn’t cleaned, the urushiol will lurk – it can cause a rash for hours, days, or even years. Another danger is smoke from burning poison ivy, which can also damage your skin, nose, mouth, windpipe and lungs if you inhale it.
It’s a myth that the fluid from a blister can spread the rash. Getty Images
Poison Ivy: How It Switches From Oil To Rash
Poison ivy rash can come in many forms, from small, red bumps to blisters or red spots. However it shows up, it almost always itches incredibly.
If you get “poisoned” you won’t know right away. It can take anywhere from four hours to 10 days for the rash to appear, depending on how much urushiol gets on your skin, how sensitive you are to it, and how many times you’ve been exposed to poison ivy.
Between exposure and itchy anxiety, your body goes through a complex process of identification and reaction. When the oil gets into your skin, the sensor cells of your immune system recognize urushiol as foreign. These sensor cells then call protection cells into the area and warn them of the invasion.
The protective cells defend your body against the intruder by attacking the urushiol in the skin. Unfortunately, some of your body’s normal skin cells are victims of this war, causing the itching and swelling of a poison ivy rash.
Their protective cells will sit near the skin for many years, guarding urushiol if it ever reappears. If so, they will remember having met this villain before, and their response is often faster and more powerful than the first time.
This rash is a type of allergic contact dermatitis – in the same family as the rashes some people get from wearing jewelry or metal belt buckles, or from using certain fragrances or cosmetics.
Learning what poison ivy looks like so you can avoid it is a crucial part of your defense. Onfokus / E + / Getty Images
Poison ivy: what to do when the damage is done
The saying “Leaves of three; Leave them be highlights the best strategy to prevent poison ivy: avoidance.
However, if you come into contact with poison ivy, the first thing to do is to remove and wash any clothing that has touched the plant.
Immediately wash your skin gently but thoroughly with soap and water. It can also help to clean under your fingernails and trim your nails short to prevent the urushiol from spreading when you scratch your skin.
Poison ivy allergic contact dermatitis almost always results in a rash that usually lasts two to three weeks before going away completely.
It will eventually go away on its own, but you can try some over-the-counter and home remedies to keep the itching and rash spread at bay. The blisters that form are not infected and usually don’t need antibiotics. However, when you scratch yourself – and it can be hard to resist – open skin can become infected.
Cool, damp compresses can help reduce itching, as can soaking in a cool bath with baking soda or oatmeal bath products. Calamine lotions or creams containing menthol can also alleviate the itching somewhat. For the first few days after exposure to poison ivy, an over-the-counter cortisone cream or ointment can be used to calm your body’s reaction and prevent the rash. Taking antihistamines like diphenhydramine at night can reduce itching slightly and has the benefit of helping you sleep better.
A visit to a doctor is usually not required for a poison ivy rash unless it spreads over large areas, becomes infected, lasts more than three weeks, or is a rare extreme case that affects your breathing.
The best attack is a good defense. When out in the great outdoors, be careful what you touch and if in doubt, if it has three leaves, leave them alone.
This article was originally published on The conversation from Arthur Samia and Marjorie Montanez-Wiscovich In the University of Florida. read this Original article here.