I've done it before as a last resort when I couldn't get tyres to seal on my MTB.
Caffelatex has instructions on the bottle for it so they deem it ok, not sure about other brands, though it says it'll only prevent small punctures (eg thorns, etc).
Haven't had a puncture since, but don't know if that's because of the sealant. Either way it was easy to do.
I've done it before as a last resort when I couldn't get tyres to seal on my MTB.
Caffelatex has instructions on the bottle for it so they deem it ok, not sure about other brands, though it says it'll only prevent small punctures (eg thorns, etc).
Haven't had a puncture since, but don't know if that's because of the sealant. Either way it was easy to do.