Ok, here's my opinion as both an AAS user and an EMS worker who deals with morbidity every day: don't chance it.
Someone else died and donated you their lungs. Your insurance company paid hundreds of thousands of dollars so that an amazing surgeon could save your life from a horrible disease. You owe it to society to cherish those lungs. Don't go and add strain to them by using AAS (because gaining weight does add strain to the major systems in your body).
Also: AAS affect your immune response. This can be a positive or negative effect depending on drugs and doses used.
You're still at an immense risk for autoimmune rejection of those lungs, which would kill you. I assume you're on a bunch of corticosteriods for immune system suppression? AAS could interfere with those.
You should be dead, but now you have a new lease on life. Don't go and risk ****ing that up over vanity's sake. Just train naturally and take it easy. Your body is in a weakened state and doesn't need the intense strain that an AAS cycle and heavy lifting would put on it.
And besides, being the recipent of a new pair of lungs (which is not a common thing) will score you way more chicks and make you far more interesting in general than an extra 20lbs of muscle ever could, if you figure out how to work that into a conversation
