drug/alcohol testing policy: effective?

"Chip Jones" wrote in message news:Ak%vd.213

Random testing in the field of professional aviation is a necessary evil.
I
firmly believe that even if we completely legalize pot someday for the
masses, we will still have to maintain a zero-tolerance random drug
testing
policy or else air safety will suffer.

It's interesting that marijuana keeps coming up in this discussion. It's the
most benign of them all, impairing people less even than alcohol. According
to a drug testing link somebody forwarded, methamphetamine use is coming up
pretty dramatically (44% increase in positive test results in the last
year?!)

I agree, though, that if pot (as an example) were legalized, it still
wouldn't belong in the cockpit. But, test for it? Do they test for the
presence of perfectly legal drugs like Benadryl which, arguably, would pose
a more severe handicap to a pilot?

I'd rather ride with a guy who smoked pot last week or went on a bender
three days ago at a bachelor party than a guy who's about to fall asleep at
the yoke because he took Benadryl two or three hours ago.

-c