[__]

Hobod provided a better solution than you did.

Working from his solution:

pawn Код:

forward Death(playerid);
public Death(playerid)
{
       new Float:Health;
       GetPlayerHealth(playerid, Health);
       SetPlayerHealth(playerid, Health-5)
       if(Health-5 <= 0) KillTimer(GetPVarInt(playerid, "timerDeath")); 
}

Then to set the timer in action:

pawn Код:

SetTimerEx("Death", 1000, true, "i", playerid);