Inclusion criteria:
Adult patients (18 years and older)
Stage 1-4 squamous cell carcinoma, nasopharyngeal carcinoma
Patients receiving a total dose of 60 Gy or more in 30 fractions with or without cisplatin
Having a maximum performance score of 0 to 2 based on the ECOG Performance Status classification.
Patient expected to survive for at least three months.
No history of oral and salivary gland diseases before starting radiotherapy.
No history of liver and kidney failure
Adequate bone marrow function (WBC count above 3000 cells per cubic millimeter of blood)
Exclusion criteria:
Known hypersensitivity or allergic reaction to sildenafil or any component of the mouthwash formulation
Patients taking nitrates (nitroglycerin or isosorbide or similar nitrates) for angina or other heart problems (due to class X drug interactions with sildenafil).
Concomitant use of strong CYP3A4 enzyme inhibitors (such as ketoconazole, itraconazole, ritonavir, and clarithromycin, erythromycin) or moderate inhibitors such as the calcium channel blocker family: diltiazem, verapamil, or the antifungal fluconazole, or any drug that has the risk of increasing the plasma concentration of sildenafil (before entering the study, the patient's medication list will be reviewed for clinically important drug interactions.
Presence of active oral infection or other inflammatory or ulcerative diseases of the oral mucosa unrelated to radiation therapy (such as aphthous stomatitis and candidiasis).
Patients who had a systolic blood pressure of less than 90 mmHg at the initial screening stage or whose blood pressure was identified as less than 90 mmHg during the study were included in the study.
Patients taking blood pressure-lowering medications such as beta-blockers or calcium channel blockers, or medications related to cardiovascular disease such as digoxin or amiodarone
Patients taking blood pressure-lowering medications such as beta-blockers or calcium channel blockers, or medications related to cardiovascular disease such as digoxin or amiodarone