REFERENCE FORMULA
Reference formula
Reference basis: 100 mL τελικού προϊόντος /100 mL final product
| Ingredient | Source quantity | Scaled quantity |
|---|---|---|
| Glycerol | 10 g | — |
| Sodium hydrogen carbonate | 1 g | — |
| Borax (disodium tetraborate decahydrate) | 1 g | — |
| Peppermint essential oil | 0.05 mL | — |
| Purified water | q.s. ad 100 mL | — |
Prerequisite formulations
No separate prerequisite monograph is listed.
Documentation
Preparation description
Colourless clear local oromucosal solution containing 10 mg/mL borax decahydrate, glycerol 10 g/100 mL, bicarbonate 1 g/100 mL and peppermint oil 0.05 mL/100 mL. It is not an oral-ingestion preparation. [1]
Action and use
Specifications
Final volume 100 mL; borax 1% w/v, not 1% elemental boron. The source requires a colourless clear solution. No pH, assay, rinse-volume or microbial limits are given. Oil separation/haze requires investigation, not an improvised emulsifier. [1]
Light
Use an amber container. Protect from strong light and keep closed to maintain the intended volatile-oil component. [1]
Air and oxidation
Limit open-bottle time and excessive aeration during mixing. Tight closure limits oil/water loss and contamination; no inert gas is specified. [1]
Water and solubility
Purified water is the principal vehicle. Do not use tap water or top up the in-use bottle with water. No measured aw or antimicrobial effectiveness result is established. [1]
Humidity
Temperature
Store below 30 °C. The method uses moderate stirring without boiling. Do not heat to force oil clarity or accelerate dissolution without a documented process. [1]
pH and compatibility
Other interactions
Ingredient-specific information
Staff protection
Use gloves, eye protection and local extraction when weighing borax. Avoid dust, ingestion and eye contact. Raw-material reproductive toxicity requires SDS-based exposure control. [3]
Risk assessment
The source gives no rinse volume or treatment duration, so “2–3 times daily” cannot establish daily boron exposure. The 1.13 mg/mL value is content, not absorbed dose. Assess volume, expectoration, swallowing, mucosal damage, age and renal function. EMA 1/3/7 mg B/day thresholds trigger age-related medical advice, not automatic authorisation [2]. [1], [2], [6]
Compounding conditions
Patient-specific preparation requires documented clinical selection and explicit rinse-volume/duration instructions. For finalV mL: glycerol 0.10 V g, each salt 0.01 V g, oil 0.0005 V mL, water toV. Small batches require demonstrated oil-measurement accuracy. [1]
BUD rationale
The source states 3 months below 30 °C in tightly closed amber packaging. The earlier of 89 days/3 months is a bibliographic ceiling conditional on exact composition and local approval of controls. No matched study or AET was identified; glycerol 10% and borax do not establish adequate preservation. If the source-specific period is not formally adopted, a separate BUD decision is needed; a refrigerated period is not invented. Any earlier raw-material expiry or documented in-use limit prevails. Editorial convention: calendar-month source periods are retained as calendar periods; the calendar-period conversion ceiling is 28 days for one month or 89 days for three months; a separately selected shorter ceiling still governs. It is a conservative conversion, not a source quotation. [1]
Prerequisites
Equipment
Balance, beaker/stirrer,100 mL volumetric flask, suitable calibrated device for 50µL oil and amber bottle. Do not replace the small liquid measure with an arbitrary drop count. [1]
Compounding method
Dissolve glycerol, bicarbonate and borax in approximately one quarter of the planned purified water with moderate stirring. Add peppermint oil and stir. Transfer into a volumetric flask, make up to 100 mL with water, homogenise and verify clarity before packing. [1]
Observations
The reference batch is 100 mL final solution as established by composition and volumetric method. No dye or surfactant is added. Historical general raw-material suggestions that would alter this colourless formula are not transferred. [1]
Container and packaging
Amber bottle with tight closure. Prominent no-swallow label and segregation from oral liquids. Use a separate clean measuring cup; no mouth contact with the bottle. [1]
Quality control
Verify salts/hydration state, calculations, final volume, complete dissolution and absence of an oil phase. Check packaging/label. Visual inspection cannot replace missing AET evidence; define the microbial-control strategy locally. [1]
Storage
Below 30 °C, closed in amber glass. Avoid heat and dilution with water. Discard if appearance changes or separation occurs; absence of visible change does not exclude contamination. [1]
Dispensing
Do not supply for unsupervised paediatric use or to a person unable to spit reliably. Pregnancy/breastfeeding and renal disease require specific medical assessment. Expectorate completely; do not swallow. Historical source frequency does not replace a defined safe volume and duration. Contraindicated in hypersensitivity to any ingredient. [1], [2], [4], [5]
Labelling
MOUTH RINSE — BORAX 1% w/v. DO NOT SWALLOW. Rinse volume/duration only as prescribed: ___. Contains peppermint oil. Batch: ___. Prepared/use by: ___. Below 30 °C, tightly closed. Keep out of reach of children. [1]
v9_controls
The numeric value is a literature reference ceiling subject to its specific conditions. No actual batch BUD has been assigned and no aw measurements have been produced. The exact formula, prerequisites, container, storage and quality evidence require approval for the actual application. The BUD clock starts when compounding begins. Use the shortest applicable supported limit and assess in-use dating separately. USP categories are a technical framework and are not presented as Greek legislation.
Sources and references
- AEMPS — Formulario Nacional: SOLUCIÓN PARA GARGARISMOS (FN/2003/PO/025)2003 source code; current standalone PDF accessed 2026PDF pp.2–3, §§3–12 and patient leafletExact formula, process, finished appearance, source dating and route-specific precautions.2026-10-14
- EMA — Questions and answers on boric acid and borates used as excipients, Rev.1Adopted 11 November 2021; published 26 July 2022pp.3–6; §3, §5 and conversion annexBoron toxicity, age-related exposure warnings and conversion factors. Excipient guidance informs safety appraisal; not authorisation of these boron-active preparations.2026-10-13
- ILO/WHO — ICSC 0567: Sodium borate, decahydrateApril 2014Chemical identity; prevention; exposure effectsCAS 1303-96-4; borax hydrate identity and occupational handling.2026-10-13
- AEMPS — FN/2003/PA/006: Bórax2003 source code; current standalone PDFPDF p.2, §§3–10Decahydrate identity; pharmacotechnical and safety information. Historical use descriptions do not override current boron safety appraisal.2026-10-13
- ABDA/AMK — Bedenkliche Rezepturarzneimittel, Stand Juni 20251 July 2025Recommendations; table entry Borsäure sowie deren Ester und SalzePrimary professional safety position: benefit–risk concerns and boron thresholds. German context, not Greek law and not a globally binding ban.2026-10-13
- Medsafe — Boron-containing excipients and fertility concerns, MARC 18610 June 2021pp.4–6, 14–18Regulatory evidence review and absorption uncertainty; its quoted 2017 warning wording is superseded by EMA Rev.1.2026-10-13
- USP — General Chapter <795> Frequently Asked QuestionsNovember 1, 2023 FAQ; rechecked 14 October 2026Questions 52, 54–56, 61, 64–66General category/extension rules only; not exact-product stability evidence.2026-10-14