Benign Paroxysmal Positional Vertigo (BPPV): Although the patient denies vertigo, BPPV can sometimes present with dizziness upon standing and positional changes without the classic vertigo symptom. The patient's complaint of lightheadedness when changing positions and the partial relief with meclizine support this diagnosis. However, the presence of tinnitus and hearing loss suggests other potential causes.

Meniere's Disease: Characterized by episodic vertigo, tinnitus, hearing loss, and ear fullness. While the patient denies vertigo and ear fullness, the combination of worsening tinnitus and partial hearing loss in one ear could suggest Meniere's, especially if the vertigo is atypical or not prominent.
Ototoxicity: Given the patient's history of taking multiple medications, including those that could potentially be ototoxic (e.g., certain antibiotics, though not explicitly mentioned, or potentially high doses of NSAIDs not mentioned), this is a consideration, especially with the symptoms of tinnitus and hearing loss.
Diabetic Otosclerosis or Cochlear Damage: The patient's type 2 diabetes with nephropathy could potentially contribute to hearing loss or tinnitus due to microvascular damage affecting the cochlea or the middle ear.

Vestibular Schwannoma (Acoustic Neuroma): A benign tumor on the vestibulocochlear nerve that can cause unilateral hearing loss, tinnitus, and balance problems. Although less common, missing this diagnosis could lead to significant morbidity due to potential for neurological deficits and impact on quality of life.
Stroke or Transient Ischemic Attack (TIA): While the patient's symptoms are chronic rather than acute, it's crucial to consider vascular causes, especially given the patient's history of type 2 diabetes and potential for vascular disease. Posterior circulation strokes can present with vertigo, hearing loss, and tinnitus.
Multiple Sclerosis: An autoimmune disease that can affect the central nervous system, including areas responsible for balance and hearing, leading to a wide range of neurological symptoms, including vertigo, hearing loss, and tinnitus.

Superior Semicircular Canal Dehiscence: A rare condition where there is an abnormal opening in the bone overlying the superior semicircular canal, leading to vestibular and auditory symptoms, including sound-induced vertigo and hearing loss.
Cogan Syndrome: A rare disorder characterized by recurrent corneal inflammation and vestibular-auditory symptoms, including hearing loss, tinnitus, and vertigo, often associated with systemic vasculitis.
Autoimmune Inner Ear Disease: A rare condition where the immune system attacks the inner ear, leading to rapidly progressive hearing loss, often accompanied by tinnitus and vertigo.