Diuretics in Meniere disease: a therapy or a potential cause of harm?

Despite the lack of clear evidence for their effectiveness in treating vertigo, tinnitus, hearing loss and aural fullness, diuretics, represent a common treatment for Meniere disease (MD), as they are supposed to decrease volume and pressure in the endolymphatic partition of the labyrinth. Our group have outlined the possibility of an adverse effect on inner ear function derived from an abrupt lowering of blood pressure: a subsequent exaggerated vasomotor response inducing local ischemia could be responsible for more or less permanent damage. The inner ear, owing both to its terminal vascular supply and to the necessity of a steady metabolism, seems a reliable target for any hemodynamic imbalance that acutely affect its perfusion. In our opinion, the complexity of the inner ear anatomy and function argues against the usefulness of diuretics to reduce endolymphatic volume, in analogy to their effect on the volemia: too many active mechanisms and "buffer" systems are involved in the labyrinth. Even considering that the finding of mean low pressure values is relatively common in subjects with MD, an attempt should be to maintain a stable blood perfusion to the labyrinth; in fact, an abrupt decrease in systemic blood pressure can trigger an adverse sympathetic reaction and transmit misleading information to the cochlear vasopressin receptors.