This can create concentrated rivers of water moving offshore. Some people mistakenly call this an undertow, but there is no undercurrent, just an offshore current. If you are caught in a rip current, don't fight it by trying to swim directly to shore. Instead, swim parallel to shore until you feel the current relax, then swim to shore. Most rip currents are narrow and a short swim parallel to shore will bring you to safety.
Alcohol can reduce body temperature and impair swimming ability.
Perhaps more importantly, both alcohol and drugs impair good judgment, which may cause people to take risks they would not otherwise take. Leashes are usually attached to the board and the ankle or wrist. They are available in most shops where surfboards and body boards are sold or rented. With a leash, the user will not become separated from the floatation device. One additional consideration is a breakaway leash.