This paper aims to determine the effect of clotrimazole lozenges in addition to soda bicarbonate mouthwash and compare it with soda bicarbonate mouthwash only, in reducing radiotherapy/chemoirradiation induced oral mucositis in patients with Head and Neck Malignancies. A randomized controlled trial was conducted. Arm A - Radiotherapy/Chemoirradiation who were randomized to receive clotrimazole lozenges and soda bicarbonate mouth wash. Arm B- Radiotherapy/Chemoirradiation who were randomized to receive soda bicarbonate mouthwash only. Fifty-six patients were accrued in the trial, 28 in control arm and 28 in study arm. Fifty-two patients completed the treatment protocol. 4 patients in control arm defaulted due to various reasons. A number of patients in the control Vs study arm of Chemoirradiation group were 16 Vs 16 and in Radiotherapy group 12 Vs 12 patients. The occurrence of Grade 3 mucositis was more in the control arm 30% vs. 40% and the onset was later among patients in the study arm (week 3). In the Chemoirradiation group requirement for analgesic (92.8% vs. 53.8%), topical anaesthetic (35.7% vs. 7.6% - significant), occurrence of mouth pain(28.5% vs. 15.3%) and Ryles tube feeding (28.5% vs. 15.3%) were less in the study arm and also tolerated more number of cycles of concurrent chemotherapy (76% vs. 14% p= 0.036). A number of patients having a break in treatment (0% vs. 42.8% -significant) and occurrence of oral thrush (32% vs. 9%) were less in study arm of chemoirradiation and Radiotherapy. Nausea and vomiting were the predominant complaints in study arm probably induced by the chemotherapy. The occurrence of dryness of oral mucosa and throat was more in study arm of chemoirradiation group but less in radiotherapy only group.Overall the addition of clotrimazole lozenges to soda bicarbonate mouthwash along with oral care protocol during treatment showed significant benefit in decreasing the incidence of oral thrush.