Itching is a very common condition in which you feel an uncontrollable desire to scratch your skin. The medical term for itching is known as pruritus. It can be localized, meaning it happens in only a certain region or skin, or it can be generalized. Itching can occur due to a variety of reasons. The causes may range from something simple such as dry skin, to something more complicated as skin cancer. Most people experience a certain degree of itching daily, but not everyone has a major underlying condition. Treatment is only required if moderate to severe itching occurs, usually in the presence of other symptoms.
Itching can be caused due to several causes. The simplest cause can be dry skin which is commonly affected by changes in weather. A number of skin conditions cause itching, including dermatitis, eczema, psoriasis, burns, scars, hives, dermatographia, scabies, lichen planus, bullous pemphigoid, shingles, etc. Itching can also be caused as a result of an allergic reaction. Allergens can be in your food, environment, cosmetic products, makeup, etc. An allergen triggers the release of histamine from your cells which leads to itching and redness.
In certain cases, itching may be caused by more complicated medical conditions such as liver failure, kidney failure, anemia, thyroid issues, diabetes, leukemia, lymphoma, multiple myeloma, etc. Many bacterial, viral, fungal, and parasitic infections can also trigger itching. Some include measles, chickenpox, hand, foot and mouth disease, filariasis, trichinosis, lice, pinworms, ringworms, insect bites, etc. Itching can also result from neurological conditions such as multiple sclerosis, shingles, meralgia, or pinched nerves. Some psychological conditions can also make the feeling worse than usual. They may include depression, anxiety, or obsessive-compulsive disorder. Itching can also occur as a side effect of some medications in certain cases.
Itching can occur at any time, but some factors can increase its risk. Extreme temperatures and humidity can influence your skin. People who have known allergies are more likely to develop itching when they contact an allergen. Even if you don’t have any known allergies but have a positive family history, your risk is still high. Some people naturally have dry or sensitive skin because it has been passed on in their genes. They may complain of itching more often than those with normal skin. Increased exposure to sunlight, air pollution, environmental toxins, or chemical irritants can also increase the risk of pruritus. Pregnant females often have a complaint of itching, especially on their abdomen. Those with a weak immune system are also at risk because they are more prone to develop skin infections.
It has been estimated that around 280 million people around the globe suffer from itching due to different reasons. Racial predominance can also play a role in certain conditions. For example, itching due to prolonged sun exposure is more common among people with light skin.
Signs and symptoms of itching can vary according to different conditions. If itching occurs due to dry skin, you may notice white scales or redness if you keep scratching. In cases of skin diseases, itching may also occur with redness, swelling, nodules, papules, blisters, or other features. Itching due to an allergic reaction occurs in a particular region or may be generalized. If you have an underlying medical condition or infection, other symptoms will also be present, including fever, pain, headache, changes in appetite, weakness, etc.
Diagnosis of the condition that is causing itching begins with a detailed history. Your doctor will ask questions about the onset, duration, severity of your symptoms, any associated symptoms, pre-existing allergies or medical conditions, use of medications, recent traveling, etc. History will be followed by a physical examination in which all the clinical symptoms are noted. If your doctor suspects a disease based on your history and symptoms, they will require particular lab tests to confirm it. Lab tests commonly performed to identify the cause of itching include blood tests, skin tests, thyroid function tests (TFTs), LFTs, RFTs, and skin biopsy if necessary. X-rays or other imaging techniques will only be required if your doctor feels the need.
Itching itself is a symptom of multiple skin diseases and medical conditions. The possible causes of itching should be differentiated based on history, symptoms, physical examination, and lab tests. Itching should also be distinguished from pain and other signs of inflammation.
Treatment of itching depends on your symptoms and their severity. If you have a mild itch due to dryness or dehydration, moisturizing your skin will be enough to reduce itching. If you have an infection or an underlying medical condition, your doctor will prescribe oral or topical medications to treat the possible cause. Lifestyle modifications are also required to decrease the occurrence of itching. These include keeping yourself hydrated, maintaining a healthy diet, keeping your skin moisturized, avoiding repetitive scratching, and maintaining a good hygiene.
Oral or topical corticosteroids are given in cases of inflammation or chronic allergies. Antihistamines can also help in relieving mild to moderate itching symptoms. If you have any infections, your doctor may prescribe suitable antibiotics, antivirals, antifungals, or anti-parasitic medications. Some antidepressants can also help with persistent itching.
Prognosis of itching depends on its cause. Most of the conditions that cause itching are treatable and can be managed with suitable medical therapy. Some chronic causes may lead to a long-term itching problem that a few lifestyle modifications can manage.
Itching can be avoided to a certain extent by keeping your skin moisturized and hydrated, using a sunscreen, maintaining your hygiene, wearing light clothes, and eating a balanced diet. Excessive smoking, alcohol intake, or drug abuse should be avoided. Keep a humidifier in your home if you have dry skin. Manage your stress or anxiety levels by daily exercise, yoga, meditation, or breathing techniques. Long hot showers should be avoided. Also, be careful while picking cosmetic products for yourself and ensure it suits your skin type.
Our clinical experts continually monitor the health and medical content posted on CURA4U, and we update our blogs and articles when new information becomes available. Last reviewed by Dr.Saad Zia on May 23, 2023.
10 reasons your skin itches uncontrollably and how to get relief (aad.org)
How to get rid of itching - ScienceDirect