How often must a resident's drug regimen be reviewed?

The correct choice indicates that a resident's drug regimen must be reviewed on a monthly basis. This frequency is essential because regular evaluations of medication can help identify potential issues such as drug interactions, side effects, or changes in a resident's condition that may require adjustments to their treatment.

Monthly reviews ensure that healthcare providers closely monitor the resident's response to medications, assess the necessity of continued use, and make timely modifications if any adverse effects or ineffectiveness are noted. This practice aligns with best practices in medication management and is often a regulatory requirement in many healthcare facilities, including nursing homes.

Regular assessments play a crucial role in maintaining the health and well-being of residents, as they support safe medication use and aim to minimize any risks associated with polypharmacy or inappropriate medication therapies.