Need Macro plz

[Elvenbane-veknilash (Elvenbane)]

I assume you mean Purify, as Dispel Magic is an offensive spell.

#showtooltip
/cast [mod:shift,@player] [] Purify Disease

If you want a more advanced version:

@Elvenbane-veknilash

Priest

Shift: Mind Soothe
Alt: Mass Dispel
Harm: Dispel Magic
Default: Purify Disease/Purify

#showtooltip
/cast [mod:shift] Mind Soothe; [mod:alt] !Mass Dispel; [@mouseover,help,nodead] Purify Disease; [@mouseover,harm,nodead] [harm] Dispel Magic; Purify Disease