Hmm... well, apple juice can make some individuals cough, but Sucralose is not an alcohol-compounded sugar replacement byproduct, so it shouldn't be the offender... the only thing I can recommend, then, is seeing if watering it down further, incrementally, helps, because it really could. Some people just cannot drink viscous drinks, and fruit juices are prone to coating the throat and irritating it, by way of coating the passage down to/slightly below the Larynx.
EDIT: Wait a minute, I just thought of something - Sodium Metabisulphite is a Sulfur compound, and Sulfur agitates asthmatics into coughing in almost 90% of cases.
So, asthma was the culprit, after all. I apologize for taking so long to identify the problem - you cannot drink drinks that contain sulfur-based preservatives, if you have Asthma, Cannon.