Itchy Skin: 9 Common Causes & What to Do

Itchy skin can occur due to skin irritation or inflammation from dry skin, sweat or bug bites. These conditions are not of serious concern, but there can be other, more serious reasons for the itching, like a fungal, bacterial or viral infection. Mental conditions, like anxiety or depression, can also affect a specific part of the body, or the whole body.

Depending on the cause, itchy skin can be accompanied by other symptoms like redness, blisters, bruising or skin lesions, all which appear as a direct result of frequent itching. It is medically referred to as pruritis. 

If you experience itchy skin, you should see your doctor or dermatologist for assessment. He or she will evaluate the kind of itching you have, possible causes, where it is occurring and whether there are other symptoms present. Based on this information, a diagnosis can be confirmed and appropriate treatment can be started. Treatment can include the use of allergy medication or moisturizing creams.

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What causes itchy skin?

Some of the main reasons for itching include:

1. Allergic reaction 

Allergies can cause intense itching, as well as other symptoms of blisters or hives, scaling skin or skin lesions.

Itching from allergies can occur in any part of the body, and happens due to skin irritation or inflammation. The most common causes of allergies are:

  • Excessive heat or sweat;
  • Big bites;
  • Irritating substances in fabrics, make-up, soaps, creams, shampoos or cleaning products;
  • Animal fur or plants;
  • Food;
  • Medication;
  • Dust or musty clothes, books or couches

Allergies can be a one-time occurrence or can occur frequently, and episodes can be mild or serious. Treatment as indicated by the doctor may be necessary.

What to do: You should wash the affected area with plenty of cold water and a gentle soap. Avoid contact with the trigger, food or irritating object. You may need to use allergy medication or corticosteroids (either as a topical cream or oral pill) as directed by your doctor. More serious cases may require a trip to the emergency room, as injectable medications may be necessary to treat the allergy.

2. Dry skin

Dry skin is most commonly caused by excessive use of soaps, by taking overly-hot or long baths or showers, or by regular skin aging. With aging, skin can become thinner and lose its capacity to produce oil and stay hydrated. Dry skin can result in constant itching, as well as irritation, peeling and even skin cracking. This type of itching is more common in the legs, arms or belly.

Other causes of dry skin include the use of some medications (e.g. cholesterol medication, opioids or diuretics), dehydration, living in cold, dry climate as well as some specific diseases (which can affect keratin formation in the skin).

What to do: You should avoid hot baths, use humidifiers and opt for hypoallergenic soaps. Moisturizers should contain ceramides, glycolic acid, vitamin E or urea. Ideally, you should consult a dermatologist about which cream is best for your skin type.

To relieve itching immediately, the doctor can recommend allergy medication like loratadine or dexchlorpheniramine.

3. Dermatitis

Dermatitis is an inflammatory skin condition that is causes by a genetic or auto-immune illness. It is usually a chronic issue, and causes constant and intense itching that can come with other skin changes.

The most common types of dermatitis are:

  • Atopic dermatitis: This is more common in children where elbows and knees bend, and can appear on the cheeks or near the ears in babies. In adults, it is seen in the neck, hands or feet. This type can be accompanied by redness, peeling or skin swelling.
  • Seborrheic dermatitis: This is associated with peeling and redness, especially at the scalp and oilier regions like around the nose, beard, eyelids and chest. It can causes itching, red spots and peeling.
  • Contact dermatitis: This can provoke intense itching as well as blisters, redness, swelling and peeling. It occurs when skin comes in contact with an irritating substance, such as jewelry or make-up.
  • Dermatitis herpetiformis: This is an inflammatory response that can cause intense itching as well as small ski blisters (which look similar to herpes lesions) and can appear on the scalp, glutes, elbows and knees. This most commonly occurs in people with celiac disease or a gluten intolerance. 
  • Psoriasis: This is a chronic skin condition that causes inflammation and overgrowth of the top layer of the skin. It is associated with bright red, peeling spots on the skin, which itch and burn.

Other more rare skin abnormalities than cause itching include nummular dermatitis, epidermolysis bullosa, bullous pemphigoid, fungal mycosis and lichen planus.

What to do: You should see a dermatologist to assess your skin lesions, and follow treatment as indicated. Treatment will depend on the type of dermatitis you have, and can be done with urea-based moisturizers, corticosteroids or allergy medication. 

4. Skin infections

Skin infections can be causes by fungus, bacteria or parasites, and can cause lesions, inflammatory reactions and itching. It can occur in different areas of the body, depending on the type of microorganism causing the infection.

Some of the most common types of skin infections are:

  • Mycosis: This causes redness, peeling and can occur at any part of the body. It arises due to fungal infections, like tinea, onychomycosis, intertrigo or tinea versicolor 
  • Cutaneous candidiasis: This infection is caused by the Candida fungas and causes skin itching, and red, moist lesions that most commonly appear within skin folds (e.g. under the breasts, in the armpits, under finger nails or between fingers), although they can appear anywhere on the body
  • Scabies: This is an illness caused by an infection of tiny mites called Sarcoptes scabiei, which cause intense itching and small, hardened lumps. This skin condition is very contagious.
  • Herpes: This infection is caused by the herpes virus. It can cause redness, and small blisters that can cause itching or pain. They are more commonly seen on the lips or genital area.
  • Impetigo: This is a bacterial infection that can cause small skin wounds that contain pus and form scabs.

These infections can be transmitted from person to person, and are usually a result of inadequate hygiene habits. They are also easily transmissible to those with weakened immune systems.

What to do: Treatment should be completed as directed by your doctor. It will depend on the microorganism causing the infection. Typical medications prescribed for skin infections include antifungals (e.g. nystatin or ketoconazole), antibiotics (e.g. neomycin or gentamicin), permetrine or ivermectin solutions for scabies, or antivirals for scabies (e.g. acyclovir). Itching can also be releived with allergy medication prescribed by the doctor.

5. Systemic diseases

There are many systemic diseases that can affect several organs at once or the body as a whole. Some of these illnesses can cause skin itching.

Some examples include:

  • Viral infections, like dengue, zika or chicken pox
  • Liver or biliary duct disease, like Hepatitis B or C, primary biliary cholangitis, alcoholic cirrhosis or autoimmune hepatitis
  • Kidney disease, like chronic renal insufficiency
  • Neuropathies, caused by diabetes, stroke or multiple sclerosis
  • Endocrine diseases, like hyperthyroidism, diabetes or mastocytosis
  • HIV, obtained through a skin infection or from an immune abnormality
  • Hematological diseases, like anemia or polycythemia vera
  • Cancer, like skin lymphoma

These illnesses can cause itching that varies in frequency and intensity from person to person.

What to do:  In these cases, treatment should be directed by a doctor, in accordance with the illness causing the itching. In some cases, the doctor may recommend using allergy medication, like hydroxine, to relieve itching.

6. Psychological illness

Itching caused by a psychological condition is also known as psychogenic pruritus. It is diagnosed by doctors who are unable to find a physical or systemic cause for itching, even after extensive investigation through assessments and testing.

This type of itching can emerge with depression, bipolar disorder, anxiety, obsessive compulsive disorder, eating disorders, drug abuse or dependency or personality disorders. Sometimes, the itching is so intense that it can cause wounds.

What to do: Treatment should be directed by a doctor in accordance with the cause, and once all systemic or dermatological reasons have been ruled out. A mental health therapist can recommend psychotherapy or treat using medications like anxiolytics or antidepressants.

6. Lupus

Lupus is a type of autoimmune disease that is characterized by the excessive production of antibodies. It can cause symptoms like irritation, redness and itchy skin. In more serious cases, the antibodies can attack organs, like the lungs, leading to chest pain and shortness of breath. 

Read more about the symptoms of lupus and what can cause it. 

What to do: Lupus is not curable, but symptoms can be managed through ointments,  corticosteroid medications, and immunosuppressants prescribed by a rheumatologist. 

7. Liver and gallbladder diseases

Some liver and gallbladder disease can lead to decreased bile flow. Bile is a fluid produced by these organs and is responsible for fat absorption. Decreased bile flow can occur with an obstruction of the biliary ducts or in the liver ducts. 

Accumulate bile in the body will lead to increase bilirubin levels. This can cause symptoms like yellow skin and eyes and itchy skin, which intensifies at night and is most noted at the bottom of the hands and feet.

Cholestasis gravidarum is a liver disease that can occur during pregnancy. It presents with the above symptoms and is diagnosed with an MRI or echocardiogram. If you suspect you may have a liver problem, check out our liver symptoms quiz to assess your risk.

What to do: Once a liver or gallbladder problem is diagnosed, the doctor may prescribe medications to stimulate the production of biliary acids that can help to regulate fat levels. During treatment, it is important to avoid consuming alcohol and caffeine. You should adhere to a low fat diet until normal fat metabolism is restored. 

9. COVID-19

Although it is rare, COVID-19 can cause the development of red or purple rashes or hives that can be quite itchy. These rashes and subsequent itching is noted in different areas of the body, like arms, legs and hands. They are generally triggered by an immune system response to eliminating the virus, and can last for 5 to 14 days. 

What to do: It is important to see a doctor for consult to evaluate the possible causes of the rashes and to recommend treatment as necessary. The doctor may recommend antihistamines, immunosuppressants, and corticosteroids. Other symptoms of COVID-19, like muscle aches and fever, can be managed with acetaminophen. 

Itching during pregnancy

During pregnancy, hormonal changes that are normal during this time can lead to dry skin, which can cause itching.

In addition, there are skin problems that can emerge or worsen during this time, such as gestational pruritus (caused by biliary duct changes) or other skin pathologies like urticaria, papular dermatitis, or gestational pemphigoid.

If your itching is persistent, you should inform your obstetrician or doctor to investigate the possible cause and provide appropriate treatment.