Risk factors for toxic multinodular goiter include individuals over 60 years of age and being female.

[5] Symptoms of toxic multinodular goitre are similar to that of hyperthyroidism, including:[5] Sequence of events:[6] Hyperthyroidism is diagnosed by evaluating symptoms and physical exam findings, and by conducting laboratory tests to confirm the presence of excess thyroid hormones.

[10] In this review it was found that the recombinant human thyrotropin-aided radioactive iodine appeared to lead to a greater of thyroid volume at the increased risk of hypothyroidism.

Thus some sources have described, or still describe, thyroid adenoma (toxic adenoma) as synonymous with toxic multinodular goiter,[11] but other sources differentiate those two as single-nodule disease versus multinodular disease (respectively) with pathogenesis that is likely differing in most cases (e.g., single neoplastic cell clone versus multifocal or diffuse molecular metabolic change).

The medical eponyms "Plummer disease" (named after American physician Henry Stanley Plummer[12]) and "Parry disease" (named after English physician Caleb Hillier Parry) have been used to refer to toxic multinodular goiter, toxic adenoma, and toxic diffuse goiter (Graves' disease); the specific entity in each patient/case is not always clear retrospectively, especially in older literature.