Final answer:
Controlled substances invoices must be maintained for a minimum of two years according to the Controlled Substances Act (CSA) and the Drug Enforcement Administration (DEA). This applies to businesses that handle or distribute controlled substances.
Step-by-step explanation:
Controlled substances invoices must be maintained for a minimum of two years according to the Controlled Substances Act (CSA) and the Drug Enforcement Administration (DEA). This applies to businesses that handle or distribute controlled substances, such as pharmacies or healthcare facilities. Keeping these invoices for the required period is important for record-keeping, compliance, and potential audits.