When it comes to avoiding painful, itchy rashes, everyone knows to steer clear of the Big Three–poison ivy, poison oak and poison sumac. But you should watch out for more than just the usual suspects, because something as simple as enjoying a poolside margarita or doing a little gardening can lead to skin irritation, rashes or worse.

Did you know…if the lemon or lime juice in that refreshing drink comes in contact with your skin, it can cause a chemical reaction that makes skin ultrasensitive to the sun (a condition called phytophotodermatitis), leading to burning, itching, stinging and even large blisters on areas of contact?

Allergic reactions can occur in some people when touching common houseplants such as chrysanthemums and Peruvian lilies, or plant bulbs such as daffodils or hyacinths. The bristly spines and small nettles or hairs on plants like cacti and thistles also contain chemicals that can irritate some people.

Foods such as chili powder and horseradish contain irritating chemicals that can cause burning, redness and hives when they touch a person’s skin. Note: The chemicals in these foods can irritate the skin in some people, but consuming them will not necessarily cause a reaction.

Self-defense: The American Academy of Dermatology (AAD) says the best defense is to avoid touching these irritants, but suggests some common-sense precautions as well, including wearing protective clothing (such as long pants, long-sleeved shirts and gloves) when working in the garden or taking a hike, and washing thoroughly after you come inside. Applying sunscreen can protect skin from the chemical reaction caused by the combination of citrus juices and the sun, as can rinsing the skin after contact.

If you do get a rash: Fortunately, most plant-related rashes can be treated with an over-the-counter or prescription antihistamine or topical steroid. However, the AAD does urge individuals to seek medical attention for a rash that doesn’t fade, that spreads near your eyes or becomes infected (it might feel warm, ooze green or yellow fluid, swell or develop red streaks), if you develop a fever or body aches or if you have any difficulty breathing.

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