I can't change what happened to me, but I can do everything within my power to keep it from happening to someone else. That way you can offer a second opinion as to whether they're sober enough to drive home. Always serve food with alcohol. Foods high in protein and carbohydrates stay in the stomach longer and slow the absorption of alcohol. Use a non-carbonated base with mixed drinks.
Carbonation speeds alcohol processing.
Serve non-alcoholic beverages as an option for designated drivers and others. Don't force drinks on your guests. They may find it awkward to refuse a host's offer. Stop serving alcohol about two hours before the party is over. If one of your guests has been drinking excessively, don't let him or her drive.