When Survival mode is active, this item increases thirst by 30 points. It also increases disease risk by 7% at the next disease check.
The highlight effect is most noticeable at night or in poorly lit areas and can be very hard to see during the day.
The effect states that it highlights living targets, but it also highlights 'non-living targets' like synths, turrets and other robots.
The effect is similar to the targeting HUD power armor helmet mod but distinct in that the helmet mod displays orange horizontal scan lines in line of sight, while this item shows a glowing purple haze even through walls or locked doors.
If added to the inventory of a companion that takes chems, such as Hancock, if the companion consumes Berry Mentats, it will also affect the Sole Survivor.
The effect for highlighting enemies lacks the correct keyword to be identified as a chem effect, it is therefore unaffected by the Chemist perk and BioCommMesh. [verified]
Being under the effects of Berry Mentats can cause friendly quest NPCs to randomly turn hostile, forcing the player to kill them, for example when confronting Initiate Clarke during Duty or Dishonor. The solution is to reload to an earlier save from before taking the Berry Mentats, or wait until the effects wear off before continuing with the quest. [verified]
The "highlight" of living creatures under the influence of Berry Mentats.