Ice reduces redness and swelling for a few hours by constricting blood vessels, but it does not kill bacteria or shrink the underlying pimple. Wrap a cube in a clean cloth and hold it to the spot for 5 to 7 minutes. Direct ice on skin causes an ice burn that worsens inflammation. Use ice as a pre-event quick fix, then layer the real treatment. A Hero Mighty Patch or Rael Miracle Patch overnight handles a surfaced whitehead. A ZitSticka Killa microdart with 2% salicylic acid handles an under-skin cyst. Ice plus a hydrocolloid patch is a reasonable 6-hour stack. For ongoing breakouts, ice does nothing — adapalene 0.1% (Differin) prevents the next round.