Which statement best describes the effect of Graves disease on local anesthetic sensitivity?

Which statement best describes the effect of Graves disease on local anesthetic sensitivity?

• A. Graves disease reduces LA sensitivity
• B. Graves disease increases LA sensitivity
• C. Graves disease has no effect on LA sensitivity
• D. LA is contraindicated in Graves disease

Answer: (B)

Graves disease alters how nerves respond to local anesthetics because hyperthyroidism upregulates sympathetic activity and changes tissue perfusion. Local anesthetics block sodium channels on nerve membranes, and their effectiveness depends on reaching the nerve and being present in an uncharged form that crosses membranes. In Graves disease, increased tissue blood flow and higher free drug fraction can allow more anesthetic to reach the nerve membranes, while heightened receptor and membrane sensitivity can make the nerve more susceptible to blockade. The combination can make the block more pronounced or occur with a smaller dose, so sensitivity to local anesthetics appears increased. It’s still not contraindicated to use local anesthesia in Graves disease, but dosing may be more effectively managed with closer monitoring and attention to potential exaggerated responses to epinephrine-containing vasoconstrictors.

Graves disease alters how nerves respond to local anesthetics because hyperthyroidism upregulates sympathetic activity and changes tissue perfusion. Local anesthetics block sodium channels on nerve membranes, and their effectiveness depends on reaching the nerve and being present in an uncharged form that crosses membranes. In Graves disease, increased tissue blood flow and higher free drug fraction can allow more anesthetic to reach the nerve membranes, while heightened receptor and membrane sensitivity can make the nerve more susceptible to blockade. The combination can make the block more pronounced or occur with a smaller dose, so sensitivity to local anesthetics appears increased. It’s still not contraindicated to use local anesthesia in Graves disease, but dosing may be more effectively managed with closer monitoring and attention to potential exaggerated responses to epinephrine-containing vasoconstrictors.