Generalized itching. no evident rash or bug bites, what to do?

Dry Skin: Generalized itching without primary skin rash most commonly caused by dry skin. Most severe during the winter months and in older people, characterized by itching in areas of dry, scaly skin. Lab work can check if there is an underlying cause: CBC/diff, liver/renal function tests, and thyroid workup. Treat with daily moisturzation and better skin hygiene. Non-sedating antihistamines for itch.

Many possibilities: This could be caused something as simple as dry skin or may represent something more complex. Try antihistamines and skin lotion. If no improvement see a physician.