Which vasoconstrictor is most contraindicated for a patient with hyperthyroidism?

Correct answer: C. Norepinephrine

• A. Levonordefrin has mixed alpha/beta activity; less potent cardiovascular effects than norepinephrine.
• B. Not all vasoconstrictors are equally contraindicated; norepinephrine is the most problematic.
• C. Norepinephrine has predominantly alpha-adrenergic activity, causing significant vasoconstriction and hypertension. In hyperthyroid patients (who already have elevated sympathetic tone and cardiovascular sensitivity), norepinephrine poses the greatest risk of hypertensive crisis. It is the most contraindicated vasoconstrictor.
• D. Epinephrine in small dental cartridge doses can generally be used with caution in controlled hyperthyroid patients.