thc is a natural antibiotic, as well as all cannabinoids.
so I don't see how smoking with a respiratory infection is a bad thing, I'd say it's a good thing as long as the infection is bacterial.
but for respiratory infections it'd be better to vape.
but yeah, I've heard hot water in a bong is a good way to smoke when you're sick.
if your bong is good enough, you can put hot water in the bottom and ice cubes in the top and hit that shit

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