A suggestion if you don't want to give up coffee entirely (I'm a fellow addict and can't do without it, get terrible headaches if I don't have at least my morning fix) - try having an espresso or cappuccino instead of a americano, as the longer coffee beans/grounds stay in contact with water, the higher the caffeine content is. So if you have a good espresso, the caffeine content will be less than that of an americano or filter coffee. Also, try using pure arabica beans (e.g. Illy), as they have a lower caffeine content. Hope that helps!