| Skin & intradermal testing (95004, 95017, 95018, 95024, 95027, 95028) | Percutaneous and intracutaneous testing, each test on its own line | Unit count matched to the tests done, capped to each payer's frequency limit and MUE, never one lumped panel |
| Challenge & patch testing (95044, 95052, 95065, 95076, 95079) | Oral food and drug challenges, patch and nasal provocation | Timed thresholds evidenced before any challenge add-on is charged |
| Antigen preparation (95144, 95145–95149, 95165, 95170) | Supplying the extract — single-dose vials, venom by count, multidose doses | Units read off the mixing log — a 1 cc aliquot per dose, ten per Medicare multidose vial, venoms tallied one by one |
| Immunotherapy administration (95115, 95117) | The injection, one versus two or more | 95117 charged once for multiple shots and joined to the antigen line only when we compounded it |
| Airway & inflammatory studies (94010, 94060, 95012) | Spirometry, pre/post bronchodilator, exhaled nitric oxide | Held clear of duplicate charges; FeNO kept within its frequency allowance |
| Visit plus procedure (99202–99215, modifier 25) | A separate E/M on a testing or injection day | Modifier 25 applied only where a distinct, documented problem is present — never a routine shot |