Allow use of expired opioid antagonists

SB 503 allows for the use of expired opioid antagonists, such as naloxone, to treat opioid-related drug overdoses. This bill grants partial immunity from liability to school employees, eligible recipients, medical practitioners, and pharmacists who administer or distribute these expired medications in good faith. It amends existing law to explicitly permit schools to stock and use expired opioid antagonists and extends immunity to school personnel, except in cases of gross negligence or intentional misconduct. The bill's purpose is to broaden access to life-saving opioid antagonist medication by permitting the use of expired doses.