Why Does My Body Itch? Dermatologists Explain All the Possibilities

You know when you get a stuffy nose, and you sit and think about all of the times you didn't have a stuffy nose and how you took it for granted? That's also how we feel when it comes to irritated, inflamed, and itchy skin. A couple of hard-to-reach mosquito bites is all it takes for us to think back fondly on all the times that our skin was calm, cool, and comfortable. 

What's more annoying is when your skin itches for what seems like no reason. One day all is well, and the next, you're ceaselessly scratching your arms and legs, trying to pinpoint a culprit to no avail. So, are you sitting here asking yourself, why is my skin so itchy? We asked four expert dermatologists for the lowdown. As it turns out, the sources of skin itchiness are varied, but there are a few that are most prevalent. Keep scrolling for some common causes of itchy skin and how to get relief.

Dry Skin

Widespread itching is often a sign of dry and dehydrated skin. Typically, skin becomes dry because it is lacking adequate sebum (an oily and waxy substance produced by the body's sebaceous glands) and natural oils, explains board-certified dermatologist Dr. Deanne Mraz Robinson. When the skin's barrier is compromised in this way, receptors in the skin think the skin barrier is malfunctioning. These receptors then react by changing the type of signal being sent, leading to the sensation of itchiness, explains board-certified dermatologist Dr. Morgan Rabach. 

If this is the case, Dr. Yoon-Soo Cindy Bae—board-certified dermatologist and founder of Cindy Bae Dermatology—recommends rinsing your skin with a gentle soap to remove any irritants. Then she suggests using a basic moisturizing body lotion or oil, which will help the skin retain moisture.

For help from the inside out, Dr. Robinson recommends aiming to drink at least half your body weight in ounces of water a day. Staying hydrated has shown to positively affect the skin's physiology. Robinson also advises steering clear of showers that are super hot or cold, suggesting you opt for a lukewarm shower instead as extreme temperatures harm and irritate the skin barrier. 

Sunburn

If you find that widespread itchiness happens only in the summer months, it may be that your skin is healing from sunburn. Sunburned skin is dry and tight, which can lead to itchiness. Sunburn not only damages the skin but also releases inflammatory cytokines, messengers that make our skin irritated and itchy, explains Dr. Robinson. In this case, preventing the burn and the itch is as easy as applying sunscreen every day.

If you need to treat a sunburn, Dr. Robinson suggests soothing the skin with a cool washcloth; it will help regulate your temperature, which may rise after a bad sunburn. You can also lather your skin in aloe vera, which will help soothe the burn and any itchiness. Finally, if topical treatments just aren't cutting it, Dr. Robinson suggests taking ibuprofen to manage any remaining inflammation. It's also important to keep sunburned skin out of the sun while it heals. If your sunburn is so bad that it's blistering, make sure to keep an eye out for any signs of infection—such as oozing. If it looks like your skin might be infected, schedule a visit with your doctor as soon as possible.

Sweat and Water

If itchiness and sweating go hand in hand, take stock of how much you perspire. According to our experts, although not super common, sweating can sometimes trigger intense itching or even hives. Perspiration, along with contact with water like when showering, swimming, or even getting caught in the rain, can lead to itchy skin in a reaction called "aquagenic urticaria," Dr. Rabach explains.

According to Rabach, aquagenic urticaria is an immune-related histamine reaction in which hives appear on the skin after the skin comes in contact with water. If you don't have aquagenic urticaria, cholinergic urticaria is another reaction that causes hives. In this case, the skin breaks out in hives because the body's "fight or flight" response is triggered, which sometimes happens when a person's body temperature increases, reveals Dr. Robinson.

"While the hives typically resolve on their own as the body cools off, it can be a frustrating condition and one you should work [on] with your dermatologist and allergist to manage properly," Robinson advises. A simple step you can take before visiting your doctor is making sure you're wearing strong antiperspirant and are showering every day, Dr. Bae adds. 

A New Product

Another possible cause of itchy skin is that you're using a product that's irritating your skin. It can be a new product, Bae says, like a detergent, lotion, or sunscreen. If you suspect one of your products is to blame, try to take note of when the itchiness comes. Does it arise after you apply your new body lotion or maybe after a spritz of perfume? Ruling out the culprit will stop itchiness at its source. It's also possible that you're allergic to a certain ingredient. "Allergic contact dermatitis is the result of the skin touching an irritant and/or allergen. After being exposed to a foreign substance, the body releases an inflammatory response that can make the skin feel itchy and irritated," Dr. Robinson explains.

This is where a visit to the doctor comes in handy. Dermatologists have the knowledge and testing abilities necessary to pinpoint the exact ingredient that may be irritating your skin. Once you know what it is, you can avoid it. Long story short: It never hurts to visit a derm. 

Hair Removal

If the itch is localized—like on your legs, underarms, or bikini area, for example—and you choose to be hair-free, it could be the result of your hair removal method. Dragging a dull blade over sensitive skin is the quickest way to irritation and itchiness. "Shaving with a dull blade can pull and twist the hair follicle, triggering irritation and inflammation," says Dr. Robinson. A dull blade that’s been lying around in your bathroom is also very likely to be harboring bacteria or fungus, which can cause folliculitis—small red bumps or white-headed pimples—Robinson tells us.

To prevent folliculitis and the irritation that comes from using a dull razor, make sure to use a sharp, clean razor when shaving, and exfoliate the skin regularly to eliminate dead skin cells. Shedding dead skin cells help to clear pores and prevent bacteria and fungus from growing in the hair follicles.

Eczema

Persistent itching may also be a sign of a more serious skin condition like eczema. "Treating the underlying disease is an important part of addressing the itch," says Dr. Adam Friedman, board-certified dermatologist and professor at George Washington University. According to Dr. Robinson, eczema is an "inflammatory response that compromises the skin barrier and causes itchy skin."

"It can be triggered by a variety of topical triggers, as well as lifestyle causes like stress and food sensitivities," he says. Many skin conditions like eczema require prescription medication from a licensed dermatologist to treat.

Psoriasis

"Psoriasis is a chronic, inflammatory autoimmune disease that causes a buildup of skin cells," explains Dr. Robinson. According to Robinson, psoriasis occurs when T cells (otherwise known as white blood cells) act as if your body is under attack—even though it's not. In response, the body begins to produce proteins that cause inflammation. The skin cells respond to this inflammation by reproducing old skin cells that it cannot shed fast enough, so these cells build up and form thick plaques that can be itchy, painful, and may even become infected.

Psoriasis can be treated with a combination of medication, a healthy diet, and stress relief measures. As Dr. Robinson explains, both emotional stress (such as feeling overwhelmed) and physical stress (such as eating dairy when you're allergic or sensitive to it) will cause the body to release a hormone called cortisol which causes inflammation. As psoriasis is an inflammatory disease, lowering inflammation levels through lifestyle changes can help curb flare-ups.

Scabies

Scabies is "an itchy skin infection caused by a tiny mite that has burrowed into the upper layer of the skin and caused inflammation," says Dr. Robinson. Scabies is contagious and is spread by prolonged skin-to-skin contact with someone who has contracted the skin infection, she explains. Symptoms include inflamed skin, an itchy rash, and skin sores. According to Robinson, scabies can be treated with a topical or oral medication prescribed by a doctor.

Hives

Hives are an "outbreak of swollen, pale red bumps or plaques on the skin that appear suddenly, typically as a result of the body's reaction to an allergen," explains Dr. Robinson. "Hives usually itch and may also burn or sting." Hives typically appear on the skin quickly and clear away fast, and are commonly caused by a reaction to a topical product, a food, or a medication that elicits an allergic reaction.

To treat hives, you have to identify the allergen, take measures to avoid it, and treat the flare-ups with antihistamines. In extreme cases, more aggressive measures like the use of an EpiPen are required, Robison says.

Mosquito Bites

Most of us know how itchy mosquito bites can be, but did you ever learn why? "When a mosquito bites you, it ingests your blood, while in turn injecting its saliva into your skin," Dr. Robinson explains. "The proteins in the mosquito's saliva trigger the immune system to react." The immune system’s reaction to the proteins in the mosquito's saliva are the raised, red, and itchy bumps we all know as mosquito bites.

Dr. Robinson recommends Corizone-10 Anti-Itch Cream ($6) for soothing itchy mosquito bites. 

Poison Ivy, Poison Oak, and Poison Sumac

Poison ivy, poison oak, and poison sumac can all lead to allergic contact dermatitis due to a sticky oil called urushiol, which causes an itchy, blistering rash upon contact with the skin, reveals Dr. Robison. If you're allergic to ivy, oak, or sumac (a type of shrub) and your skin touches it, the urushiol oil will stick to the skin within minutes of contact, and a rash will develop over several days.

“Red, raised blisters typically appear within 12–72 hours of contact with the urushiol resin. [The rash] peaks within one week but can last as long as three weeks with lesions appearing gradually over this time,” Dr. Robinson tells us. "Based on the severity of your skin’s reaction, your dermatologist may prescribe a topical or oral steroid to reduce inflammation or an antibiotic if the area has become infected," she adds.

The Final Takeaway

Dr. Friedman recommends always checking in with an expert if skin itchiness is a chronic issue. "[Even] when you are dealing with itch without a rash, seeing a dermatologist is central to proper care. In many cases, the generalized or focal itch may be due to overactive nerve signaling, but it could be associated with something more nefarious," he warns.

Incessant itching could be damaging your skin more than you know. "I've had patients that scratch to the point that they bleed," Dr. Bae reveals. "If you take an object with an edge—like your nails—and you rake it over your skin over and over again, there will be wear and tear even if it is small," she explains. Friedman agrees: "Scratching both disrupts the skin barrier (our army to the outside world) and induces more inflammation, as it's a physical injury. Scratching also leaves its mark through discoloration and scarring even after the cause has been identified and managed," he concludes.

To avoid the damage caused by scratching, prevention and treatment of the itching are key. The fastest way to identify the cause and figure out a treatment plan is with the help of a dermatologist. Your skin will thank you for it.