My son is approaching his A levels. He has seen an ad for some mints that claim to improve concentration - they are just expensively branded caffeine tablets. He wants to get some for the exams. He is not a tea/coffee drinker. I don't want him to get the tablets but he is 18, so will get them if he wants to. I'd be concerned they might give him the jitters if he has too many. I don't know if his school would even allow them in exams - hopefully not. Would you be concerned?