Answer: No. Marijuana is considered an illegal drug, and medical marijuana is not allowed onboard, during transfers to and from ships, inside terminals, during shore excursions, or when visiting private islands.
Illegal drugs or substances will be confiscated, and appropriate action will be taken, which may include removal from the ship and involvement of law enforcement and other authorities. Additionally, foreign governments at ports of call enforce strict laws for drug possession. Guests found in violation of such laws are subject to arrest and prosecution by foreign authorities (and possibly the United States or other authorities) and may be prevented from re-boarding the ship.