One of the simplest ways is to use groups (/help groups) with /enable and /disable.

Example:

Code:
#mygroup on

on *:TEXT:*:#: {
  .disable #mygroup
  .timer 1 5 .enable #mygroup

  ; do your event stuff here
}

#mygroup end


You can do the same with a %variable that gets unset after a certain amount of time (see /set -uN) and an if guard:

Code:
on *:TEXT:*:#: {
  if (%mygroup_disabled) return
  set -u5 %mygroup_disabled $true

  ; do your event stuff here
}

- argv[0] on EFnet #mIRC
- "Life is a pointer to an integer without a cast"