The red plump lip belongs to a  Asia girl.
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Over-the-counter lip plumper products use an irritant that causes the lips to swell temporarily, giving a fuller, pouty appearance. But while you want that “bee stung” look, you don’t want the inflammatory reaction of a real bee sting. Some of the ingredients used as an irritant include cinnamon, menthol or mint, ginger, niacin--even chili pepper. While the intent is to makes blood vessels dilate, which increases blood flow to the lips, you may have a more intense reaction to the plumping ingredient, causing a red, rashy look or even painful swelling.

Itchiness

When applied, a lip plumper will always cause a slight tingling and burning sensation. But if the itchiness, often described as an uncomfortable spiky feeling, does not subside, then you may be reacting to the ingredient niacin. Niacin is used to increase blood flow and causes flushing of the superficial capillaries of the skin, which can result in uncomfortable itchiness.

Redness

Redness usually takes the form of a skin eruption or rash, which breaks out after contact with the irritant in the lip plumper. Generally, the symptoms are merely redness, swelling or itching in a small area, although sometimes they may resemble the effects of a common cold or hay fever.

Burning

If a lip plumper burns, clean it off immediately. A slight burning sensation is common, but if your lips feel like they are on fire, or if you feel like you've been punched in the mouth, remove the product completely, and toss the tube.

Swelling

The lips are supposed to swell if the plumper is working as advertised, but you don’t want anaphylactic shock-like swelling or blisters. The most common plumper ingredient is cinnamon oil. Cinnamic aldehyde, component of cinnamon oil, is known to cause allergic dermatitis. Symptoms include a rash, intense swelling and redness of the affected area. Menthol is a mild irritant that could be causing the problem. Benzyl nicotinate is also added to give your lips the tingling feeling that lip plumpers are supposed to provide, but that could cause excessive swelling.

Cracking & Peeling

Constant use of a lip plumper can cause the lips to become very dry. To help avoid dry, cracked lips, look for a lip plumper that includes a moisturizer in its ingredients, such as shea butter, sunflower oil or aloe vera. Another drawback to using a lip plumper with harsh ingredients is a few days after using it, you may experience peeling of the irritated skin on the surface of the lips.