Tough position. Tell your doc and he'll document AAS usage in your chart. Insurance company gets ahold of your chart and boom, your premiums skyrocket. It's complete bullshit. It's up to you whether you tell him or not. I'm not advising you to hide your usage from him, but I will say that if you don't want him to know, just schedule an appointment complaining of one month of fatigue, malaise (vague feeling of discomfort), lack of appetite, and joint aches. He'll get liver function tests. Only problem is, he may want to do further testing if they come back abnormal. You can always decline further testing and say you'd rather have the tests repeated in a month or so and see if they resolve on their own.
Or you can just tell him your using. Tell him there is less risk with AAS usage that with breast augmentation (he can look it up....it's true) and the benefits are the same, improve aesthetics and self confidence.