Knee itch quiz
Take a quiz to find out what's causing your itch.
Are you experiencing itchy knees? Itchy knees can be caused by a variety of underlying conditions that range in severity, from common conditions like eczema to rare conditions like dermatofibroma. Read more below to learn 7 possible reasons you're experiencing itchy knees and how to treat it.
9 most common causes
7 knee itch causes
This list does not constitute medical advice and may not accurately represent what you have.
Scabies is a rash caused by the microscopic human itch mite. It burrows into the top layer of skin to feed and causes severe itching and irritation.
The mite spreads through direct contact or through infested bedding or furniture. It can infect anyone, though most susceptible are:
- Sexually active young adults.
- Anyone with a weakened immune system.
- Patients in nursing homes and other long-term care facilities.
Symptoms include intense itching, especially at night, and a rash of tiny red bumps. Scratching may cause the rash to form sores, scales, or crusts. The rash most often forms between the fingers, in the folds of the wrists and elbows, and any place normally covered by clothing.
It is important to get treatment because the scratching can cause an infection in the skin. In children, mites can cover nearly the entire body.
Diagnosis is made through physical examination and skin test.
Treatment involves a prescription for skin cream. Everyone who has come into contact with the affected person must be treated, even if they show no symptoms.
Top Symptoms: vaginal itch or burning, vulvovaginal redness, feeling itchy or tingling all over, butt itch, elbow itch
Urgency: Primary care doctor
Psoriasis causes an overgrowth of surface skin cells, creating a red, scaly, itchy, and painful rash.
It is believed to be an autoimmune disorder that causes the body to attack its own healthy skin cells. It may be genetic in origin but triggered by anything that further strains the immune system, such as infections, skin injury, alcohol consumption, obesity, smoking, and stress.
Symptoms may come and go in cycles lasting weeks or months. They include red patches of thickened skin, sometimes with gray-white scales; dry, cracked, bleeding skin; stiff and swollen joints; and thickened, misshapen nails.
It is important to see a medical provider for care, because psoriasis can interfere with quality of life. It is associated with higher risk of arthritis, heart disease, diabetes, and other conditions.
Treatment involves different combinations of topical medications, oral medications, and phototherapy with natural or artificial light. Lifestyle changes such as improved diet, quitting smoking, and managing stress are very helpful in many cases.
Top Symptoms: itchy rash, red or pink, rough patch of skin, rash with well-defined border, painful rash, scaly rash
Symptoms that never occur with psoriasis: fever, black-colored skin changes, brown-colored skin changes, blue-colored skin changes
Urgency: Primary care doctor
Non-specific knee rash
A rash is an area of irritated or swollen skin. Often, rashes are unidentifiable and some variation of normal. For example, scratching one's arm causes it to turn red (which is caused by mast cells releasing chemicals into the local area), but that's completely normal.
At this time, you do not need treatment for this rash. If it worsens, you may need to consult a physician.
Molluscum contagiosum, also called "water warts," is a common, benign, viral skin infection. It causes a rash of bumps that may appear anywhere on the body.
The virus spreads through direct contact with the bumps, including sexual contact. It also spreads through touching any object that an infected person has handled, such as clothing, towels, and toys.
Most susceptible are children under age 10. Other risk factors include dermatitis causing breaks in the skin; a weakened immune system; and living in warm, humid regions under crowded conditions.
Symptoms include a rash of small, pale bumps with a pit in the center. The rash is usually painless but may become reddened, itchy, and sore.
Diagnosis is made through physical examination.
In some cases, treatment is not needed and the condition will clear on its own. However, if the bumps are unsightly or are present in the genital area, lesions can be removed through minor surgical procedures or treated with oral medication or topical agents.
Insect bite from a chigger
Chiggers are mites that feed on humans and animals only while they are larvae, or their infant form. People can contract chiggers when they contact infected grass. feed for three to four days on a piece of skin, and secrete a fluid that causes intense itching.
You should go to a retail clinic to be treated, as household remedies aimed at killing the mite are unlikely to be effective. The infected area should be kept clean with soap and water. A hydrocortisone cream or local anesthetic may be helpful to reduce the itching. You should avoid scratching the wounds!
Top Symptoms: lower leg itch, lower leg redness, knee itch, ankle itch, ankle redness
Urgency: Phone call or in-person visit
Eczema (atopic dermatitis)
Atopic dermatitis, also called eczema, dermatitis, atopic eczema, or AD, is a chronic skin condition with an itchy rash.
AD is not contagious. It is caused by a genetic condition that affects the skin's ability to protect itself from bacteria and allergens.
AD is most often seen in infants and young children. Most susceptible are those with a family history of AD, asthma, or hay fever.
Infants will have a dry, scaly, itchy rash on the scalp, forehead, and cheeks. Older children will have the rash in the creases of elbows, knees, and buttocks.
Without treatment, a child may have trouble sleeping due to the intense itching. Constant scratching may cause skin infections and the skin may turn thickened and leathery.
Diagnosis is made through physical examination, patient history, and allergen skin tests.
AD cannot be cured, but can be controlled through prescribed medications, skin care, stress management, and treatment of food allergies. Those with AD often have allergies to milk, nuts, and shellfish. Keeping the skin clean and moisturized helps prevent flareups.
A dermatofibroma is a fairly common skin growth that usually appears on the lower legs, but may appear anywhere on the body. These mole-like growths are benign (noncancerous.)
The cause is not known, though a dermatofibroma may appear after a minor injury. The growths are not contagious.
Dermatofibromas are most common in adults and are rarely found in children.
Symptoms include a hard, raised growth that is red, pink, or brown and less than half an inch across. They are usually painless but may be tender or itchy, and may appear alone or in groups.
Any new growth on the skin should be seen by a medical provider, especially if the growth is very dark in color or changes its shape or appearance quickly.
Diagnosis is made through physical examination and sometimes biopsy.
A dermatofibroma does not require treatment unless it is interfering with clothing or is unsightly. They can be surgically removed, though this will leave a scar and the growth may eventually return.
Benign skin growth
Benign skin growths are very common and virtually everyone has some form of them. "Benign" means the growth is not cancerous and not harmful. Some of these growths have genetic origins, and for some the cause is not clear.
Common types are:
- Birthmarks, may appear as flat "stains" in the skin or as raised clusters formed of tiny blood vessels.
- Moles, small irregularities that originate in the pigment-producing cells in the skin. They can be almost any shape or color but are normally no larger than one-quarter of an inch across.
- Skin tags, little irregular flaps of skin, like a flattened mole attached on only one side.
- Keloids, a dark, fibrous form of scar tissue that forms after a skin wound, either from trauma or from surgery.
As a person ages, more changes may appear in the skin. Most are benign, but any unusual or suspicious skin growth should be checked by a medical provider. The growth can be removed if it is unsightly, interferes with clothing, or proves to be malignant (cancerous.)
Allergic contact dermatitis of the knee
Allergic contact dermatitis means the skin has touched something that provoked an allergic reaction, causing inflammation and irritation.
"Contact" means the allergic reaction came from touching something, not from consuming something. The first exposure to the substance sensitizes the immune system, and then the second exposure actually causes the symptoms.
The most common causes of allergic contact dermatitis are:
- Nickel, a metal often used in belt buckles, the buttons on pants, and jewelry, including piercing jewelry.
- Poison ivy.
- Various types of perfumes, including those founds in soaps, fabric softeners, and detergents.
- Of course, there are many more.
Symptoms include red, itching, scaling, flaking skin that may be painful due to the irritation and inflammation.
Diagnosis is made through first avoiding contact with any suspected substance, to see if the dermatitis clears. Patch testing can be done if the results are not certain.
Treatment involves fully avoiding the allergy-provoking substance and using topical steroid cream as prescribed. Cool compresses and calamine lotion can help to ease the discomfort.
Top Symptoms: knee redness, knee itch, scabbed area of the knee
Symptoms that always occur with allergic contact dermatitis of the knee: knee redness
Irritant contact dermatitis
Irritant contact dermatitis means a skin reaction that is caused by directly touching an irritating substance, and not by an infectious agent such as a bacteria or virus.
Common causes are soap, bleach, cleaning agents, chemicals, and even water. Almost any substance can cause it with prolonged exposure. Contact dermatitis is not contagious.
Anyone who works with an irritating substance can contract the condition. Mechanics, beauticians, housekeepers, restaurant workers, and health care providers are all susceptible.
Symptoms include skin that feels swollen, stiff, and dry, and becomes cracked and blistered with painful open sores.
A medical provider can give the best advice on how to heal the skin and avoid further irritation. Self-treatment can make the problem worse if the wrong creams or ointments are used.
Diagnosis is made through patient history, to find out what substances the patient comes into contact with, and through physical examination of the damaged skin.
Treatment involves avoiding the irritating substance if possible. Otherwise, the person can use petroleum jelly on the hands underneath cotton and then rubber gloves.
Top Symptoms: rash with well-defined border, itchy rash, red or pink, rough patch of skin, painful rash, red rash
Symptoms that always occur with irritant contact dermatitis: rash with well-defined border
Symptoms that never occur with irritant contact dermatitis: fever, black-colored skin changes, brown-colored skin changes, blue-colored skin changes
Questions your doctor may ask about knee itch
To diagnose this condition, your doctor would likely ask the following questions:
- Did you possibly brush into poison ivy, poison oak, or poison sumac?
- Any fever today or during the last week?
- Do you have a rash?
- Do you have skin changes anywhere that skin touches or rubs other skin (such as the back of the knee, inside of the elbow or wrist, or the armpit)?
Self-diagnose with our free Buoy Assistant if you answer yes on any of these questions.
Knee itch symptom checker statistics
People who have experienced knee itch have also experienced:
- 14% Lower Leg Itch
- 11% Upper Leg Itch
- 6% Ankle Itch
People who have experienced knee itch were most often matched with:
- 66% Eczema (Atopic Dermatitis)
- 33% Allergic Contact Dermatitis Of The Knee
People who have experienced knee itch had symptoms persist for:
- 28% Less than a day
- 26% Less than a week
- 24% Over a month
Source: Aggregated and anonymized results from Buoy Assistant.
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