Background: Xerostomia, or dry mouth, is a prevalent condition among older adults and has significant implications for oral and systemic health. It is associated with impaired chewing, swallowing, and speech, and increases the risk of oral infections, dental caries, and gum disease. Xerostomia may also contribute to malnutrition and aspiration pneumonia.

Objective: This study aims to evaluate the effectiveness of an enzymatic-containing mouth spray (Oral7®) on xerostomia symptoms, unstimulated salivary flow rate, and oral health-related quality of life (OHRQoL) in older patients with xerostomia.

Methods: A single-center, randomized, double-blind, placebo-controlled trial will be conducted at Hospital Universiti Sains Malaysia from August 2025 to July 2026. Eligible participants aged 60 and above with self-reported xerostomia will be randomly assigned to receive either Oral7® Mouth Spray or a placebo spray for four weeks. The primary outcome is the mean change in Summated Xerostomia Inventory (SXI) scores between groups from baseline to post-intervention. Secondary outcomes include changes in unstimulated salivary flow rate using the sialometry technique and OHRQoL measured by the Geriatric Oral Health Assessment Index (GOHAI) at baseline and three months post-intervention. Data will be analyzed using SPSS version 29.

Conclusion: This trial will provide evidence on the efficacy of Oral7® Mouth Spray in alleviating xerostomia symptoms and improving salivary function and oral health-related quality of life in older adults, potentially guiding future clinical management of this condition.

Inclusion Criteria:

• Aged 60 years and above
• Patients with often or always having dry mouth/xerostomia by asking single-item xerostomia question: "How often does your mouth feel dry?" (Adakah mulut anda sering merasakan kekeringan?). The response options were "Never (Tidak Pernah)," "Sometimes (Kadang-kadang)," "Often (Kerap)," or "Always (Sentiasa/Sepanjang masa)."
• Patients who are taking nutrition orally
• Patients who are able to speak
• Patients who are physically fit to take oral spray on their own.

Exclusion Criteria:

• • Patients on salivary substitutes for the past one week

  • Oral condition that required immediate attention such as mucosal or gingival bleeding, orofacial swelling, oral pain and oral ulcer.
  • Patients who are deaf and mute
  • Those with mental disabilities or documented cognitive deficits that would impair their ability to answer questions independently.