Iodine 131 treatment is generally safe. After treatment, there is usually only transient, mild gastrointestinal discomfort and a feeling of swelling and pain in the neck, with rare cases of nausea, diarrhea, and dry mouth. However, it usually does not cause serious toxic side effects such as vomiting, hair loss, bone marrow and gonadal suppression. Yang Hui, Department of Nuclear Medicine, Henan Cancer Hospital usually does not cause infertility and does not increase the chance of other tumors. 131I short-term side effects of nail clearing treatment (from question 29 of 2012 Chinese guidelines for thyroid nodules and differentiated thyroid cancer) The therapeutic dose of 131I forms direct radiation damage to DTC lesions, residual thyroid tissue, adjacent tissues and other normal tissues and organs that can take up iodine. It leads to varying degrees of radioinflammatory reactions. Common side effects in the short term (1-15 days) after nail cleaning treatment include weakness, neck swelling and throat discomfort, dry mouth and even swollen salivary glands, altered taste, nasolacrimal duct obstruction, upper abdominal discomfort and even nausea, and urinary tract damage. Most of the above symptoms appear within 1-5 days of clear nail treatment and often resolve on their own without special treatment. Some studies have shown that radiation damage to the salivary glands can be reduced by taking acidic candy, chewing sugar-free gum, massaging the salivary glands, or rehydration during 131 I treatment [77,78]. However, a recent prospective, randomized, double-blind, controlled study reported that the dose of radiation absorbed by the salivary glands was not significantly altered by vitamin C at different times after the use of 131I [79]. Measures such as drinking plenty of water, urinating more often and taking laxatives may help to reduce radiation damage to the abdominal and pelvic cavities, but the possibility of triggering electrolyte disturbances needs to be noted. In patients with comorbid other chronic diseases and/or advanced DTC, persistent hypothyroidism combined with damage from 131I after nail clearance, the underlying disease condition may worsen in the short term, requiring close observation and timely management. In addition, patients may experience some psychological changes, such as boredom, anxiety, insomnia, fear, etc., in the short term after nail clearing treatment, which are not a direct result of 131 I damage, but originate from some factors during treatment implementation (e.g. radiation protection isolation, gradual worsening of hypothyroidism and other disease effects, etc.)