Join Date: Jan 2003
Location: Manchester, United Kingdom
Programs: Hilton Gold, Priority Club Blue, SPG Gold, Sofitel Gold, FB Ivory, BA Blue
Posts: 8,467
I had no problems at LAX and proof of prescription wasn't asked for. At check in , I was given a plastic bag to put it in and advised to present it to the TSA (who didn't have a problem with it).
Edited to add: I took a salbutamol aerosol on board.