PUBG (PlayerUnknown's Battlegrounds) is a popular online multiplayer battle royale game that can have various side effects on players. Some potential side effects of PUBG include:

1. Addiction: PUBG can be highly addictive, leading players to spend excessive amounts of time playing the game and neglecting other important aspects of their life, such as work, school, and social relationships.
2. Aggressive behavior: The intense and competitive nature of PUBG can cause players to become more aggressive, both in-game and in real life, which can lead to conflicts and negative consequences.
3. Poor physical health: Playing PUBG for long periods can lead to physical health problems, such as eye strain, headaches, back pain, and poor posture.
4. Poor mental health: Excessive gaming can negatively impact mental health, leading to issues such as anxiety, depression, and social isolation.
5. Disturbed sleep patterns: Playing PUBG late at night or for long periods can disrupt sleep patterns, leading to insomnia, fatigue, and decreased productivity.