Itch – What is It? How Can We Help?
by Dr. Michael McKelvey
As a dermatology and allergy practice, itch is one of the most common complaints we see, and also one of the most poorly understood symptoms. Hardly a day goes by without a frustrated patient visiting us, suffering through itch, while trying any number of ineffective treatments.
Today we break down the three most common causes of itch and how to properly treat them. As a practice that offers both dermatology and allergy services, we are uniquely positioned to offer comprehensive evaluations and treatment of virtually any itchy disorder.
1. Inflammatory Itch
Inflammatory itch is by far the most common cause of itch and can result from a number of different skin disorders. Inflammatory rashes are typically slow forming and gradually evolve over the course of several days to weeks. Contact dermatitis, such as poison ivy, or irritant dermatitis, such as eczema, are frequent offenders. Other causes include insect bites, medication reactions, rashes triggered by the sun, and autoimmune disorders.
Regardless of the cause, the common link for all of these conditions is that the itch is mediated by an inappropriate inflammatory reaction within the skin. Steroids are the main tool that we have to treat inflammation. Hydrocortisone cream is the only topical steroid available over the counter, and while it can be effective for mild cases, it is not particularly strong. More aggressive inflammatory conditions require stronger options including prescription topical medication, oral steroids, or steroid injections. Skin biopsies and allergy testing are helpful in determining the cause of inflammatory itch
2. Histamine-Induced Itch
Histamine release into the skin, most commonly presenting as hives or urticaria, is the next most common cause of itch. These rashes are characterized by localized swelling in the skin that evolves much more rapidly than inflammatory itch, typically coming and going over the course of hours. Hives can be triggered by a number of exposures including viral infections, allergies, medications, and physical stresses on the skin. Because of the unique cause, they require a very specific treatment–antihistamines. Classically, Benadryl was the mainstay of hive treatment, but newer antihistamines that don’t cause drowsiness and last longer are now the preferred treatment for urticaria (Claritin, Zyrtec, Allegra). Allergy testing is often beneficial in determining the cause of hives.
3. Neuropathic Itch
Neuropathic itch is the least common cause of itch. It is often difficult to diagnose because it does not present with a skin rash. In this condition, nerves are inappropriately sensitive and send itch signals to the brain without a normal trigger.
Neuropathic itch can be seen in patients with neuropathy, nerve entrapments (i.e. carpal tunnel), liver or kidney dysfunction, or blood cell disorders. Therapies that distract from the uncomfortable sensations, such as cooling lotions containing menthol, can be helpful for this type of itch. Often, medication with direct activity against the overly sensitive nerves can be prescribed for relief.
Why it’s not “just an itch”
Studies have shown that severe itch can decrease the quality of a person’s life even more than chronic pain. If you’re itching, you don’t have to suffer. Call the office for a comprehensive evaluation and let’s begin treating your itch with appropriate therapy today.