Oaksterdam staff, doctors, etc. repeatedly cite that bongs, hookahs, water pipes, etc. are intrinsically unhealthy by creating a bacteria-loving environment (unless, I suppose, you sterilize after each use.) If you are a patient with any amount of suppressed immunity, suggest you stay far away from these devices.

Pipe smoking is next in the worst category due to the high temps and potential for tiny particles being deposited deep in lungs.

Rolled joints are better because they are filtering the smoke and supposes the user isn't puffing till the roach disappears (smoking the filter.)

Mad is correct. Vaporizers are best / safest for inhaled methods.