Defeating Warwick
How do I defeat warwick on pvp because it is impossible to get a kill as I always keep getting killed from him. I play as Caitlyn as she is the most useful champion to me and I buy powerful items to try to defeat him but I kill the other enemy champions apart from him. I have noticed that he always suppressed Caitlyn and keeps healing when he damages a minion or champion. Someone give me advice on how to defeat warwick as I can kill him on Co-op vs AI

Quick Silver Sash.
which can lead to a
Mercurial Scimitar, which deals as much damage as Bloodthirster.
The best thing about these two items is that of it's active.
When you press it any kind of negative effec, debuff (Zed's ultimate, Fizz's ultimate) or CC (stuns, slows, silences, blinds) gets removed. This completely counters Warwick's ultimate.
It has, I think 45 MR which is as much as a Banshee's Veil, great against an enemy team that has a lot of magic damage.
Warwick deals a lot of damage and most likely more often will deal more magic damage because of Sated Devourer.
Makes you 100% harder to kill by Warwick or any mages or AP assassins. This item has a similar effect as QSS but you can't choose which one it will block. It give you zero damage though so buy it after you've got your main damage items.