The feeling of breathlessness one gets when a romantic gesture is made. Nothing can be done to stop the feeling which is likened to a gas canister exploding in the chest.
Once you have 'Love Asthma' nothing can be done to cure this feeling - it will hit you from time to time, rendering you useless and unable to carry out normal day-to-day activities.
Jimmy: 'You are the single most beautiful, thoughtful, intelligent, witty girl in the entire world and I really cant wait until you're my wife'
Lulu: 'Now I have Love Asthma'