The only drug that ever consistently made me feel paranoid while under the influence was cocaine. That stuff is terrible and I'll never do it again!
When I first smoked weed it made me paranoid, but I was 14 and worried that my parents would find out and I'd be in trouble more than anything else.
Now the most paranoid I get on it is when I'm driving at night, and I have headlights behind me. Makes me move the sack from my pocket to my sock, because I know that they'd NEVER find it there
(if it really is cops, and if I even get pulled over and searched).