Final answer:
Thyroxin, also known as thyroid hormone, should be monitored in a person on amiodarone.
Step-by-step explanation:
When a person is on amiodarone, the hormone that should be monitored is thyroxin, also known as thyroid hormone. Amiodarone is a medication used to treat certain heart rhythm problems. It can affect thyroid function and lead to changes in thyroid hormone levels. Monitoring thyroid hormone levels is important to ensure that the medication is not causing any adverse effects on the thyroid gland.