A Trial of Magnesium Dependent Tinnitus

Descriptions of tinnitus date back to the time of ancient Egypt, yet science has failed to unravel the mysterious underlying mechanisms that produce these subjective auditory perceptions of sound. These perceptions may be manifestations of damage resulting from noise exposure, ototoxicity, or other abnormal conditions of the auditory system. However, many individuals have idiopathic tinnitus for which no specific cause can be determined. Although often presenting in conjunction with hearing loss, the magnitude of hearing loss does not necessarily correspond with the severity of tinnitus. In addition, some individuals reporting tinnitus experience concomitant hyperacusis. This relationship suggests these processes may be linked by underlying imbalances at the level of the hair cell. The possible influence of magnesium and its antagonist, calcium, has been discussed in the literature as a contributing factor in the mitigation of noise-induced hearing loss, ototoxicity, and the hyperexcitability of the auditory system (Cevette et al, 2003). Permanent and temporary changes in auditory function have been linked to nutritional deficiencies of magnesium. Magnesium deficiency has resulted in increased susceptibility to noise-induced hearing loss (Ising et al, 1982; Joachims et al, 1983; Joachims et al, 1987; Scheibe et al, 2000), ototoxicity (Vormann and Gunther, 1993), and hyperexcitability (Kruse et al, 1932; Cevette et al, 1989; Bac et al, 1994) of the auditory system.

The recommended daily allowance (RDA) for magnesium in adults is 4.5 mg/kg (Saris et al, 2000); however, all age groups of Americans fall short of the RDA for magnesium by 100 mg daily (Standing Committee on the Scientific Evaluation of Dietary Reference Intakes, 1997). This lack of appropriate magnesium intake may have negative consequences. For example, the putative magnesium mechanism within the auditory system involves a metabolic cellular cascade of events. Specifically, magnesium deficiency leads to increased permeability of the calcium channel in the hair cells with a consequent over-influx of calcium, an increased release of glutamate via exocytosis, and overstimulation of N-methyl-D-aspartate receptors on the auditory nerve fibers. Recent studies of both noise-induced hearing loss and idiopathic sensorineural hearing loss have suggested that magnesium supplementation may lessen the severity of tinnitus in patients. Magnesium improved hearing recovery and lessened tinnitus in patients with idiopathic sudden hearing loss (Gordin et al, 2002). More recently, Nageris et al (2004) showed in a well-controlled study that magnesium was a relatively safe and convenient adjunct to corticosteroid treatment for enhancing the improvements of hearing in acute-onset sensorineural hearing loss at a dose of 4 g. The protective effect of magnesium in noise-induced hearing loss has been previously reported (Ising et al, 1982; Scheibe et al, 2000).

Despite these encouraging findings, no controlled study has examined the effect of magnesium supplementation for patients with moderate to severe tinnitus.

• Dietary Supplement: Magnesium
  Magnesium 532 mg a day
• Other: Placebo
  matching form/dosage

• Experimental: Magnesium
  Intervention: Dietary Supplement: Magnesium
• Placebo Comparator: Placebo (Sugar pill)
  Intervention: Other: Placebo

Inclusion criteria:

• Normal Kidney function (last checked within 6 months)
• An audiogram within the past 6 months
• Mayo Clinic patients who live in Phoenix area

Exclusion criteria:

• Any participant with decreased kidney function within past 6 months
• Current treatment with Lithium
• Tinnitus rating with 0, 1, or 2 on the 0-10 Tinnitus scale