This prospective study is a randomized, double-blind, placebo-controlled Phase 3 clinical
trial of oral D-methionine (D-met) to reduce noise-induced hearing loss (NIHL) and tinnitus.
The goal of the study is to develop a safe, oral pharmacological agent to augment physical
hearing protectors for noise exposures that exceed the protective capabilities of ear plugs
and/or muffs. The study population is a cohort of Drill Sergeant (DS) instructor trainees
during and 22 days after their 11 day weapons training. The primary objective of this study
is to determine the efficacy of D-met in preventing NIHL or reducing tinnitus secondary to a
minimum of 500 rounds of M-16 weapons training occurring over an 11 day period.