Yes, radioactive iodine can cause side effects such as temporary worsening of hyperthyroid symptoms, hypothyroidism, swelling and pain in the neck, radiation sickness, and salivary gland problems. To learn more, connect with me at drjeromepuryear.com. Thank you!

Neck tenderness and swelling.
Nausea.
Swollen salivary glands.
Loss of taste or taste change.
Dry mouth/insufficient salivary production.
Dry eyes.
Excessive tearing from the eyes.