I've been trying to figure that out too. I've never smoked, but was a bad drinker. I quit 10 months ago. When I drive I don't feel calm. My legs get fidgety, my arms shake as they hold on to the steering wheel. I start to gulp a lot and start getting the panic all over me. I hate and just wish I could drive normal like I use to. I just started taking Prozac, so I hope it helps out.