I don't know if either one of these will do what you are looking for, but it's the best I can offer. I actually use both of them.
1. Benecast-k
-- One of the many "can't live without" things this mod does is it puts a button next to the Player, Party, Pet, and Target frame if one of those people is afflicted with a Debuff (Curse, Poison, Disease etc...) that YOU can cure.
So if I'm playing a Shaman and I'm in a group fighting spiders and some of my party members get poisoned, a little button shows up next to their name. When I click on it, it automatically casts "Cure Poison". No thinking involved. I just click whichever button shows up.
(I highly recommend Benecast-k for ANYONE that plays ANY character with spells, because they ALL benefit from it in one way or another. It does a LOT more than what I mentioned above. That example is just a little itty bitty thing compared to all the other headaches it saves you!
)
http://www.curse-gaming.com/mod.php?addid=1458
2. Ralaks Needy List
-- This is actually kind of redundant if you have Benecast, but I've found it useful so far. See I have my Benecast buttons as small as they go, so I don't always notice when the Cure Poison button pops up. With Needy List I get the same effect on a bigger scale. If myself or someone in my group needs to be healed or to be cured, a fairly good size box will pop up on the list and it's coloring lets you know what is wrong. If you need to cast a Cure, it also provides a spell button next to the box for you to click, so you don't have to go looking for it.
Due to Needy List being set with bigger boxes, I am more likely to see it pop up on my screen than I am to see a Benecast button show up when we're in the heat of battle.
http://ui.worldofwar.net/ui.php?id=1156
Hopefully one or both of those will be able to accomplish what you are looking for
*Arouin