A brain implant which inhibits nociception, or pain sensation. While it does allow the user to accomplish more, it turns out pain has a purpose. When you don't feel it, you can get hurt really bad really easily.
A Painstopper is a brain implant that will completely eliminate a colonist's pain and any pain-related mood effects.
In the base game, the painstopper can only be obtained via trade.
Pain reduces consciousness which in turn reduces manipulation, moving and talking. Thus, it directly and significantly impacts almost every activity a pawn can perform. It also inflicts a significant mood debuff.
Most kinds of pain are temporary and not worth installing a Painstopper for that reason alone. However, pain from scars is permanent, and some painful diseases such as Sensory Mechanites can linger for long periods of time. Note that colonists with the Masochist trait get a mood bonus from pain, and this will also be removed by the Painstopper. Also note that with the Royalty DLC , psycasters recover neural heat quicker with pain. It also completely eliminates the downside of the Wimp trait, though in exchange for other risks.
The painstopper can also be a huge boon in combat. As the pawn is injured, the stat losses to pain stack with those of the injuries themselves and significantly decrease the DPS of a pawn. The painstopper prevents these losses and dramatically improves DPS output for the length of the fight. Additionally, as the Pain Shock Threshold is never crossed, meaning the pawn can fight longer as well.
This carries a significant risk, as colonists with this implant will not go into shock from pain and will keep fighting until death (most common case), or be incapacitated from serious leg, spine or brain injury. While maintaining high damage output and longer can help end fights sooner, before they risk fatalities or win otherwise unwinnable fights, it is important to keep an eye on them so you can get them to retreat in time before they receive fatal damage, especially while hunting or in melee.
Alternatives to reduce pain such as Go-juice and the Painblock psycast can be used to gain the benefits temporarily for either combat or maximizing skill success chance, without the long term risk. However, these come with their own drawbacks including addiction, chemical damage, short duration and cost.
Installing the painstopper requires a medicine skill of 4.