Itching is the one skin symptom that can drive one mad. It is a sensation that is unique to skin, which produces an uncontrollable urge to scratch. There are specific substances that are produced by skin cells, immune cells, and nerves that mediate the sensation of itching. Extrinsic and intrinsic stimuli activate receptors on skin cells, causing them to release chemical transmitters that activate nerves in the skin.
In addition, immune cells are stimulated to release a variety of itch inducing substances such as histamine, opioid peptides, leukotrienes, prostaglandins, acetylcholine, interleukin-31, substance P, vasoactive peptides, and thymic stromal lymphopoietin. This is why antihistamines do not always help with itching, as non-histamine neurotransmitters are involved.
Itching can be a symptom of primary skin disease, an underlying systemic medical condition, medication, a neurologic problem, stress, anxiety, chemical or mechanical environmental causes, contact dermatitis, skin barrier dysfunction, as well as a combination of all or some of the above.
The key is determining which itch producing molecular pathway(s) should be targeted to obtain relief. A comprehensive physical examination and laboratory tests are part of the initial evaluation. Adhering to gentle skin care precautions to minimize irritation and inflammation are part of treatment goals.
Bring all your current skin care products, cleansers, and medications to your appointment. Provide a list of what you have tried including oral medications with a timeline and response description.