yeah, I've never said to a doctor that I would like more of any given drug, The advice above is good. Just explain how the xanax has helped you but that the dosage isn't helping you enough. Explain how it helps you and how the lack of effectiveness has kept you from living a quality life.
When it comes to prescribing benzo's it's all about quality of life. Show how how your increased anxiety disrupts your life and prevents you from doing xyz. a big factor will be you job, sleep, big major lifestyle issues, your family, etc. .5 mg strikes me as an obscenely low dose anyways. But remember do not even have it in the back of our mind that you want more xanax, you are just giving your doc an update on how the treatment has been going. The xanax is helping you but you still have a lot of anxiety about some things and although the xanax has helped you some, it just ain't enough.
Also it is reasonable to wait a month after starting your new medication to see how it effects you before you make any other medication changes. If you really need to, just take more than prescribed and get your refill early.If you need it, you need it. You doctor has to allow for you to get refills. Once you are addicted it is criminal for your doctor to cut you off. However that strategy, if employed to obviously get more pills will really pi$$ off your doctor to the point of hime kicking you to the curb afterwards.