Interesting. I must admit I would naturally say 'empathetic', on the analogy of 'sympathetic'. The Oxford English Dictionary gives both. The first recorded usage of 'empathic' is from 1909, as a technical term in psychology. 'Empathetic' goes back to 1932 - it first appeared in America - and the context of the earliest citations seems to be rather broader and less technical than that of 'empathic.'
I shall try to remember to say 'empathic' in future, which I agree sounds classier.