This study aims to investigate the effect of Hericium Erinaceus on clinical patients with hearing impairment and possible mechanisms. Subjects with hearing impairment will be enrolled and randomly divided into experimental or control group supplemented with Hericium Erinaceus (430 mg/kg/day) or placebo, respectively for eight months. Basic characteristics will be evaluated at baseline by questionnaire. The hearing, liver and kidney functions, and neurotrophic factors will be examined at baseline, 4th month and 8th month.

This study aims to investigate the effect of Hericium Erinaceus on clinical patients with hearing impairment and possible mechanisms. Subjects with hearing impairment will be enrolled. Inclusion criteria were 50 to 79 years old with symmetric sensorineural hearing loss, subjective sensorineural tinnitus, and all frequencies differed of ears less than 15 dB. Exclusion conditions were patients with abnormal liver and kidney function, normal hearing, severe and very severe hearing loss, no tinnitus or non-subjective sensorineural tinnitus, moderate or more cognitive impairment, patients unable to understand the details of this study or patients unable to co-examine, history of alcohol or drug abuse, history of high ambient noise exposure, bone tone air gap of pure tone hearing threshold greater than 10 dB, and audiogram 4 kHz air conduction threshold greater than 8 kHz, 20 dB airway threshold, hearing impairment before age 30, and inability to understand the details of this study. Participants will randomly divide into experimental or control group supplemented with Hericium Erinaceus (430 mg/kg/day) or placebo, respectively for eight months by a prospective, randomized, double-blind approach. Basic characteristics will be evaluated at baseline by questionnaire. The status of hearing, and CBC, GOT, GPT, BUN, Creatinine, NGF and BDNF expressions in blood will be examined at baseline, 4th month and 8th month.

Inclusion Criteria:

• Patients aged 50 to 79 years old with symmetric sensorineural hearing loss, subjective sensorineural tinnitus, and all frequencies differed of ears less than 15 dB.

Exclusion Criteria:

• Patients with abnormal liver and kidney function, normal hearing, severe and very severe hearing loss, no tinnitus or non-subjective sensorineural tinnitus, moderate or more cognitive impairment , patients unable to understand the details of this study or patients unable to co-examine, history of alcohol or drug abuse, history of high ambient noise exposure, bone tone air gap of pure tone hearing threshold greater than 10 dB, and audiogram 4 kHz air conduction threshold greater than 8 kHz, 20 dB airway threshold, hearing impairment before age 30, and inability to understand the details of this study.