Ok if I understand what you are asking, you are asking how to remove a status effect that a mob cast on you that has negated one of your buffs. Example you have haste cast on you and a mob casts slow on you, which removed your haste, correct? There are 3 actions you can take to remove the slow effect. The first most preferred is to cast or have your WHM/SCH cast haste on you again - this will remove the slow and recast haste on you again at the same time. 2nd would have mage cast Erase on you to remove the status effect of slow. 3rd would be to use a bottle of Catholicon, a Cleric's Drink or a Vicar's Drink. The 1st drink is a temp drink you get out of a chest, the 2nd 2 can be purchased. You can research them on FFXIAH.com.
I decided to poke around in the FFXIcolpieda.org database and discovered a huge list of mob cast status effects and the actions that should be taken to remove the effect. I've been playing since 2006 and would have loved to have found this list long before this, especially since I play WHM 75% of the time. I pasted the link below......btw, there is NO CURE for the spell DEATH and next to no chance for curing Doom.....and I have some hysterical stories about large group Doom deaths as witnessed from the back line. Skyfiredancer (talk) 12:51, May 16, 2015 (UTC)