release), which encompasses "slow release", has relevance because if
it is controlled-release, it is specially-formulated and thus the
tablet or capsule (usually but not always) cannot/should not be
split, otherwise the release is disturbed. I think this is a main
value of bothering to record that there is something "special" about
a particular drug form, the other value would be that SR is typically
given less often than the "regular" form, but you cannot tell just
from the "SR" label, it might be only once a day, or it might be more
often (e.g. some l-dopa/carbidopa).