[Subjective tinnitus]
Subjective tinnitus is more common than [objective tinnitus], but diagnosis of the underlying cause is more difficult. The differential diagnoses of subjective tinnitus are medication and toxic exposure, metabolic abnormalities, pathologic condition in the peripheral (cochlear) or central (retrocochlear) pathways, [anxiety], [depression], and [dental disorders]. Metabolic abnormalities include hypothyroidism, hyperthyroidism, hyperlipidemia, anemia, and zinc deficiency. The initial workup of a patient should include a /*CBC*/, /*fasting glucose*/, /*triglycerides*/, /*cholesterol*/, and /*thyroid-stimulating hormone*/. Pathologic conditions of the ear associated with subjective tinnitus include [otosclerosis], [chronic suppurative otitis media], [Meniere disease], [presbycusis], and [noise-induced
hearing loss].