In the manual we can read:
"- characters don't lose any experience points, skills points, items or blessings when dying in the drome
- mana potions, health potions, arrows, bolts, and runes are not being consumed upon use (other consumable items like rings, amulets, cupcakes, but also imbuements will be used regularly)
- there is no skill or experience gain when fighting in the drome
- fights in the drome do not lower a character's stamina
- spells that use soul points are deactivated" 1
However, what will happen with my Experience boost if I have one active? Will I lose some of the time of my Experience Boost?
1. Tibiadrome manual: https://www.tibia.com/gameguides/?subtopic=manual§ion=combat