Painkiller

 is a deathstreak in Call of Duty: Modern Warfare 2. It divides all given damage by three when the user spawns for the third time without getting a kill (second with Hardline Pro). It only lasts for ten seconds before the player's maximum health returns to normal (this does not include knives, riot shields, or fall damage, however). While Painkiller is in effect, the player's screen is tinged yellow with a pill showing how many seconds are left in the deathstreak reward. When shooting a player with this deathstreak, a small pill will appear below the crosshairs. This deathstreak replaces Juggernaut perk from previous Call of Duty games. It is a little less effective since it is temporary, but it gives a much greater health bonus, dividing all damage given from a weapon by 3. In most game modes, the player will respawn away from the action, making this deathstreak useless though this perk can be useful if an enemy kill streak is in use such as a Chopper Gunner or AC-130, giving the user enough time to react and find cover. It is more helpful in crowded games like Free-for-All where players often spawn close to each other, and small maps are more common.

The extra health may confuse experienced players who know exactly how many shots are needed to kill a non-painkiller enemy, causing them to instinctively stop firing before actually killing the painkillered player and sometimes even reloading, giving the painkiller player a chance to escape or to turn around and shoot back.

Tips

 * Painkiller will prevent most one-hit-kills from a silenced sniper rifle round to the head in Hardcore.
 * Even a direct hit with a grenade launcher will not kill someone with Painkiller.
 * Painkiller will not prevent the user from dying if hit by an AC-130's 105mm Howitzer or 40mm gun.
 * The Riot Shield (much like the knife) ignores the effects of Painkiller and will still kill an opponent in 2 hits or 1 hit in Hardcore.
 * Using a Tactical Insertion to spawn near an anticipated concentration of enemies (such as a flag in Domination) will help you enter combat before Painkiller expires.
 * In smaller maps (ex. Scrapyard and Rust), Painkiller can be very effective if used as the player will definitely run into an enemy within the ten second time limit.
 * Painkiller is very effective when getting out of a spawn trap (very common in Domination games). Also, if the enemy team has sent someone into the player's spawn location (the one person normally won't change the spawn positioning), Painkiller can be an effective way of stopping the player in the spawn point of continuously killing people right off spawn.
 * It is very effective in taking down snipers considering a sniper rifle will take numerous shots to kill the individual. Not only will this give the player time to take cover, but considering that the sniper will probably miss more shots as the player gets closer, the player should have time to line up a shot to effectively take out the sniper.
 * A good tactic to use against painkiller is that when you see a person with it, run into cover and wait out the 10 seconds that it lasts.
 * Online, this Deathstreak is looked down on by many experienced players due to the strength of it, the ease of achieving it, and how soon it is unlocked. It grants what many consider an "unfair" advantage over players, albeit temporary.

Trivia

 * Online painkiller is often referred to as "jugger-noob," "pain pills," "medicine," or "being on the pill," or just "pills."
 * It is not used much due to the reasons to said above. Also, it is uncommon due to the fact that it only lasts ten seconds, meaning that it will most likely expire before one reaches combat on larger maps.
 * If you stick an enemy with a semtex with painkiller active, they will not die.
 * The SPAS-12, M1014 and Ranger shotguns can all kill a Painkiller player instantly without the Stopping Power perk if at a very close/point blank range, as the SPAS and M1014 do a max of 320 damage per shell, and the Ranger does max 450.

Also the Painkiller deathstreak does not have an effect on falling damage. You will die when you don't have commando pro.