General malpractitioners are zombie doctors found on Braindeath Island who work for Captain Donnie. They are found in the dungeon below the dormant volcano with a number of 'Rum-pumped' crabs that they have created through mutation after injecting Braindeath 'rum' into the local crab population.
Along with the 'Rum'-pumped crabs, these are aggressive to players of any level and are much stronger than their combat level suggest, especially as the syringes they throw are highly accurate and can poison you. To limit damage, it is highly recommended to bring Super antipoison and use Protect From/Deflect Ranged.
As they are zombies and therefore undead, a Salve amulet or Salve amulet (e) can be worn to increase your damage and accuracy against them.