The specific treatment of isodense nodular shadows in the left adrenal region is related to the nature of the nodule, which may be due to diseases such as adrenocortisolism, primary aldosteronism, and congenital adrenocortical hyperplasia. The nodule can be treated by medication or surgical excision as prescribed by the doctor. 1. Adrenocorticotropic hyperplasia: It is caused by excessive secretion of glucocorticoids (mainly cortisol) by the adrenal cortex due to various reasons. Imaging examination may show isodense nodular shadow in the left adrenal region. Treatment can be prescribed oral medication Mitotane tablets, Metipranolone tablets, etc. to inhibit the synthesis of cortisol. 2. Primary aldosteronism: it is mainly caused by excessive secretion of aldosterone by adrenal cortex, and imaging may show isodense nodular shadow in the left adrenal region. Surgery is feasible for treatment. 3. Congenital adrenocortical hyperplasia: congenital gene mutation can lead to certain adrenocorticotropic hormone synthetizing enzyme defects in the body, thus triggering adrenocortical hyperplasia, and the imaging examination can suggest that the left adrenal region isodense nodular shadow. Treatment can be prescribed oral hydrocortisone tablets, cortisone acetate tablets and other drug replacement therapy to improve the symptoms. Patients with isodense nodular shadows in the left adrenal region should choose the correct treatment under the guidance of the doctor.