A Homeopathic Remedy I suggest "Euphrasia" drops, or if not available Euphrasia tablets.
Stick to natural remedies whenever possible, ESPECIALLY any eye treatment,
You did not state how long since he did this.. as with all things, sooner the better, better healing.
Probably any alcohol in the wash is the greatest irritant, and will take time to resolve in any event, but helped on the road to recovery with GOOD Intention too. On a lighter note hope he SEES the folly of his actions, this is how we all learn.
Best o' British