Bipolar disorders are among the most significant neuropsychiatric conditions, affecting many people annually worldwide. Despite being accepted as one of the most effective treatments for this illness, lithium, like any other medicine, is associated with a number of adverse effects. Lithium’s adverse effects are divided into acute and chronic categories. The acute effects include renal, thyroid, and parathyroid dysfunction and hypercalcemia, while the chronic effects involve parathyroid hyperplasia and adenoma, among others. This paper will discuss the physiopathology, prevalence, symptoms, diagnosis, and treatment of lithium’s adverse effects.