Would A Doctor Ever Prescribe HIV Meds (Complera) To HIV

Would a doctor ever prescribe HIV meds (Complera) to HIV negative patients with immune systems that are just very weak? Do HIV meds benefit the immune system in any way in a person without HIV, just with some other type of immune system problem? My friend who takes Complera claims she doesn't have HIV but just takes it because her immune system is bad. It's none of my business except for the fact that we've shared piercings and razors. Should I be worried? Can HIV be transmitted through sharing piercings and razors?