Potassium Nitrate has been used as a desensitizing agent to treat dentinal hypersensitivity. The effectiveness of a potassium nitrate is evaluated both in the form of a toothpaste and a mouthwash in a clinical study. Thirty patients were assessed using evaporative stimuli and thermal stimuli and response was evaluated using Visual Analogue Scale at baseline, at 2 weeks and 4 weeks. The patients were divided into group I: fifteen patients who used toothpaste containing 5% potassium nitrate, sodium fluoride, xylitol and triclosan, group II: Fifteen patients who used mouthwash containing 3% potassium nitrate, sodium fluoride, xylitol and triclosan . The results of both the assessment methods indicated that potassium nitrate toothpaste as well as mouthwash showed statistically significant decrease in the sensitivity score on a Visual Analogue Scale. This was effective in reducing the symptoms of dentinal hypersensitivity when used either as toothpaste or as a mouthwash. But, there were no statistically significant differences between the groups, although both were effective in the treatment of hypersensitivity.