You don't have to consult a doctor before taking any supplements. Iron is just one that the body can store and you can take too much of it.
B-vitamins and C are water soluble and the extra gets peed away.
L-lysine is generally well tolerated (unless you have a pre-existing kidney problem). I never took more than 2000mg a day, but I know some people have taken up to 6000mg a day (divided into several doses).