A health care professional is caring for a patient who is about to begin levothyroxine (Synthroid) therapy to treat hypothyroidism. Which of the following instructions should the health care professional include when talking with the patient about taking the drug.

a) Take levothyroxine with calcium supplements
b) Take levothyroxine on an empty stomach
c) Take levothyroxine with grapefruit juice
d) Take levothyroxine with high-fiber foods