The California Poison Control System (CPCS) is the certified statewide regional poison control center for California, and provides immediate, free and expert treatment advice and referral over the telephone in case of exposure to poisonous or toxic substances. In the United States, callers can get immediate access to their regional poison control center by calling the toll-free number 1-800-222-1222 anytime, 24 hours a day, 7 days a week, 365 days a year.