[syn: distressing, distressful, disturbing, perturbing, troubling, worrisome, worrying]
The Collaborative International Dictionary of English v.0.48:
Worrisome \Wor"ri*some\, a.
   Inclined to worry or fret; also, causing worry or annoyance.
   [1913 Webster]
WordNet (r) 3.0 (2006):
worrisome
    adj 1: not reassuring; tending to cause anxiety [syn:
           unreassuring, worrisome] [ant: reassuring]
    2: causing distress or worry or anxiety; "distressing (or
       disturbing) news"; "lived in heroic if something distressful
       isolation"; "a disturbing amount of crime"; "a revelation
       that was most perturbing"; "a new and troubling thought"; "in
       a particularly worrisome predicament"; "a worrying
       situation"; "a worrying time" [syn: distressing,
       distressful, disturbing, perturbing, troubling,
       worrisome, worrying]
Moby Thesaurus II by Grady Ward, 1.0:
37 Moby Thesaurus words for "worrisome":
   aggravating, annoying, bothering, bothersome, chafing, disquieting,
   distressful, distressing, disturbing, exasperating, fretting,
   galling, harassing, importunate, importune, irking, irksome,
   irritating, pesky, pestering, pestiferous, pestilent, pestilential,
   plaguesome, plaguey, plaguing, provoking, teasing, tiresome,
   tormenting, troublesome, troubling, upsetting, vexatious, vexing,
   wearisome, worrying