Taste Buds

Taste buds are located on the circumvallate and fungiform papillae of the tongue and to a lesser extent on the tonsillar pillars, base of the tongue, soft palate, pharynx, and larynx. Hypogeusia - reduced ability or ageusia - loss of ability to taste sweet, sour, bitter, or salty substances is an early and frequent complaint associated with head and neck radiotherapy. Histologically, taste buds show signs of atrophy at 10 Gy. Higher doses will obliterate the taste buds.¹³

Taste acuity may decrease by a factor of 1,000 to 10,000 due to direct radiation damage to the taste buds and/or secondary to impaired salivary function and mucositis. Perception of acid and bitter is affected early, whereas sweet and salt acuity is affected as treatment continues. Restoration of taste sensation usually occurs within 2-4 months following radiotherapy; however, some patients may experience a life-long alteration in or loss of taste perception.¹³