Pruritus

An unpleasant cutaneous sensation that elicits the desire to scratch, mediated by specific pruriceptive neural pathways distinct from those of nociception. Possible causes are dermatologic factors (dry skin, eczema, psoriasis, contact dermatitis, scabies, lice, insect bites, fungal infections, bacterial infections), systemic disease (liver failure, kidney failure, hyperthyroidism/hypothyroidism, anemia, polycythemia vera), neurological disease (herpes zoster, pinched nerves, multiple sclerosis), psychogenic factors (stress, anxiety, depression, OCD), medications (opioids, antihypertensive), and enviromental (chemicals, wool fabrics).