What is your policy for when a LAG raises pre-flop?

[KSOT]

Let's say someone who raises 18% of the hands raises from MP. Would you cold call 2 bets in LP with hands that are normally only worth limping in with? Would you 3-bet him more often than you normally might?

I think doing so has really been hurting me lately. I just hate folding decent hands to what is quite often a raise with something pitiful like A8o.