I was treated in the UK for PTSD following an accident and a series of fairly horrible incidents over the previous twenty years. I think I knew what was up even before my medical was pulled and I was sent to see Prof Cunningham at the CAA in Gatwick. I had lived with full blown PTSD for two years and although outwardly seemed ok inside I was in a right mess.
Six months of Gordon Cunningham's treatment saw me back to flying and a further six months got the two crew restriction lifted and certificate of sanity removed from my license.
PTSD is like a monster living in the back of your mind all the time. The treatment I had was gentle, in parts and pretty bloody in others. One point of interest for me was that when the two crew stipulation was removed I was told that a person who had had PTSD and responded fully to treatment was more likely to be able to deal better with high stress, traumatic events than a person who had never had such an event before.
Don't lie on your application. Getting caught may lead to a medical check, but may also lead to an employer questioning your probity and getting rid of you.
In the case of Heathrow Director I would have thought ADHD was almost an essential in his job!
SND