Zinc Mouthwash for Radiation Mouth Sores: Does it Help?

randomized-controlled-trial PMID: 36864527

Quick Summary: A study found that using a zinc sulfate mouthwash, or a mouthwash with herbs, helped reduce painful mouth sores (oral mucositis) in people getting radiation for head and neck cancer. These mouthwashes worked better than a common mouthwash called chlorhexidine.

What The Research Found

Radiation therapy for head and neck cancer can cause painful mouth sores. This study looked at whether different mouthwashes could help. The results showed that:

Zinc sulfate mouthwash significantly reduced the severity of mouth sores and pain.

A polyherbal mouthwash (containing chamomile, peppermint oil, Aloe vera, and honey) also significantly reduced mouth sores and pain.

Both zinc and the polyherbal mouthwash worked better than a standard mouthwash (chlorhexidine) and a placebo (a "dummy" mouthwash).

Study Details

Who was studied: 67 people with head and neck cancer undergoing radiation therapy.

How long: Participants used the mouthwashes for 6 weeks and were followed for 7 weeks.

What they took: Participants were randomly assigned to one of four groups:

Zinc sulfate mouthwash
Polyherbal mouthwash
Chlorhexidine mouthwash
Placebo mouthwash (normal saline)

What This Means For You

If you are undergoing radiation therapy for head and neck cancer, this research suggests:

Talk to your doctor about using a zinc sulfate mouthwash or a polyherbal mouthwash to help prevent or reduce mouth sores.

These mouthwashes may help reduce pain and make it easier to eat and drink during treatment.

Chlorhexidine mouthwash may not be as effective.

Study Limitations

Small study: The study only included 67 people, so more research is needed to confirm these findings.

Short-term: The study only looked at the effects for 7 weeks, so we don't know if the benefits last longer.

More research needed: The exact amounts of the ingredients in the polyherbal mouthwash weren't specified.

Talk to your doctor: Always discuss any new treatments with your doctor before starting them.

Key Findings

The study found that zinc sulfate mouthwash and a polyherbal mouthwash (containing chamomile, peppermint oil, Aloe vera, and honey) significantly reduced radiation-induced oral mucositis (OM) severity scores and pain intensity in head and neck cancer (HNC) patients undergoing radiotherapy. Both interventions outperformed chlorhexidine (CHX) and placebo (normal saline) from weeks 2 to 7 of treatment (P < 0.05). Post hoc analysis confirmed zinc sulfate and polyherbal mouthwashes were more effective than placebo at all follow-up timepoints, while CHX showed no significant benefit.

Study Design

This was a double-blind, randomized controlled trial (RCT) involving 67 HNC patients receiving radiotherapy. Participants were randomly assigned to one of four groups: zinc sulfate (n=17), polyherbal (n=17), chlorhexidine (n=17), or placebo (n=16). Interventions were administered over 6 weeks, with weekly follow-up assessments for 7 weeks using standardized tools (WHO Oral Mucositis Assessment Scale, Visual Analog Scale).

Dosage & Administration

The zinc sulfate group used a 0.2% zinc sulfate mouthwash (exact concentration inferred from context), while the polyherbal group received a formulation with chamomile, peppermint oil, Aloe vera, and honey. The control group used Vi-one 0.2% chlorhexidine, and the placebo group used normal saline. Participants rinsed with 10 mL of their assigned mouthwash for 1 minute, twice daily, and spat it out post-rinsing.

Results & Efficacy

OM Severity: Zinc sulfate and polyherbal groups showed significantly lower OM scores (measured by WHO/OMAS) from weeks 2–7 compared to CHX and placebo (P < 0.05).
Pain Reduction: Both zinc and polyherbal groups reported reduced pain intensity (VAS scores) during weeks 2–7 (P < 0.05).
Comparative Analysis: Post hoc tests revealed zinc sulfate and polyherbal mouthwashes were superior to placebo at all timepoints but CHX was not. No direct comparison between zinc and polyherbal efficacy was provided.

Limitations

Small Sample Size: Only 67 participants, limiting statistical power and generalizability.
Short Duration: Follow-up lasted 7 weeks; long-term effects beyond this period are unknown.
Self-Reported Compliance: Mouthwash use was self-administered, risking inconsistent adherence.
Unspecified Polyherbal Composition: Exact concentrations of chamomile, peppermint oil, Aloe vera, and honey were not disclosed.
Lack of Mechanistic Data: The study did not explore biological pathways underlying zinc’s or polyherbal effects.
No Funding Disclosure: Potential conflicts of interest or biases were not addressed.

Clinical Relevance

For HNC patients undergoing radiotherapy, zinc sulfate mouthwash may serve as an effective, low-risk intervention to mitigate OM severity and associated pain, comparable to polyherbal formulations. The results suggest avoiding chlorhexidine, which performed no better than placebo. However, larger trials are needed to confirm these findings and establish optimal dosing. Patients should consult healthcare providers before integrating zinc into care plans, as topical formulations may interact with other treatments. This study supports zinc’s role in mucosal protection but does not address systemic zinc supplementation or its effects in non-cancer populations.

Study: https://pubmed.ncbi.nlm.nih.gov/36864527/