Not all hair loss is allergy related!
This is a male, neutered, 3 yr old standard Schnauzer who was seen @dcaseattle for progressive hair loss that started around January 2022. The dog is not described to be itchy, although he does roll around on his back outside, occasionally. He was prescribed antibiotics and administered an anti itch medication (Cytopoint) with no improvement.
Notice the non-inflammatory nature of this hair loss, most pronounced on around the lower back and flanks! Dogs who have skin infections will generally have pustules, crusting, and circular areas of hair loss (epidermal collarettes).
Given the non-inflammatory hair loss and failure to regrow hair, and lack of itching, age of this dog, a low thyroid level was suspected and test results helped confirm this disease. Simple thyroid supplementation should help correct this problem!