Q: I’ve had this constant itch under my shoulder blade. What could it be?
A: A number of things can cause an itchy back, notably dry skin or a skin disease such as eczema or psoriasis. But there’s also a curious condition called notalgia paresthetica, involving chronic itching below the scapula (shoulder blade), typically on one side, most often the left. There may also be tingling, pain, or numbness in that spot, and the itchy patch of skin may be hyperpigmented. It’s thought to result from impingement of nerve roots that emerge from specific vertebrae (a type of neuropathy), and it may indicate degenerative changes in the spine.
If the itch continues, see your doctor. Though hard to cure, possible remedies include capsaicin cream (from hot chili peppers), acupuncture, transcutaneous electrical nerve stimulation (TENS), muscle relaxants and other drugs, and even botulinum (Botox) injections. Exercises that increase range of motion in the shoulder and strengthen back muscles may also help.