Final editorial decision
Final evidence decision: no product-specific study was found establishing a numerical BUD for this exact in-house formulation and container. Prefer the exact required pharmacopoeial material from an approved supplier, with an acceptable lot CoA, dating and after-opening instructions. Different pharmacopoeial formulas and methylated laboratory variants are not automatically interchangeable. In-house production requires a volatile-compatible aw assessment and written method/matrix safety suitability. Low aw does not establish solvent retention, chemical stability, seal integrity or peroxide control. No arbitrary 180-day period is assigned. This is a completed reference monograph, not certification of a released batch. This record does not specify a commercial pyroxylin grade or assay basis. Before any preparation, obtain evidence for dry-polymer content and the identity/amount of wetting agent, reconciled with the final specifications. Do not treat 5 g of unspecified wetted material as 5 g dry polymer or dry the material to correct the arithmetic. Same-session use does not remove this requirement.
Required evidence
- Define the exact pharmaceutical pyroxylin grade, dry-polymer assay basis and identity/amount of wetting agent. Reconcile material balances with final specifications of 5.0–6.0% w/w pyroxylin and 17.5–21.0% w/w anhydrous ethanol.
- Exact identity/composition of the required pharmacopoeial material, specification, actual lot CoA, supplier dating/instructions and a suitable tight container. Another pharmacopoeial formula or methylated laboratory variant is not presumed equivalent.
- For the in-house final mixture, establish the aw category using a method resistant to volatile-solvent interference and written safety/suitability confirmation for ether and the actual matrix.
- Suitable controls for ether/ethanol loss, closure integrity, appearance, applicable assays/residue and film formation. Apply fire and peroxide controls according to the material and supplier instructions.
Closure criteria
- Pyroxylin assay basis and solvent balance remain real prerequisites before any in-house preparation. Do not dry pyroxylin to correct the arithmetic. Same-session use does not remove this prerequisite.
- Procurement and routine acceptance of the exact required grade closes the material-selection question; it does not automatically establish new dating after mixing, modification or repacking.
- Low aw resolves microbial-category uncertainty only. It does not establish solvent retention, chemical stability, closure integrity or adequate peroxide control.
- Publish this monograph as a final specialist reference without a new numerical stock BUD. Actual use requires supported quality and a safe process. Same-session use does not replace identity, composition and safety requirements.
Scope
Final editorial decision dated 14 October 2026. This is not a certificate of laboratory results or actual batch release.
Sources and references
- USP General Chapter <795> FAQs, November 1 2023Questions 52, 60, 61, 62, 63; printed pp.11,14
- ANSM: Collodion, Formulaire national 1994pp.1–2, content limits; ethanol test; storage
- Addium/AQUALAB manufacturer: TDL2 volatile-sample water activity methodMeasurement principle, volatile samples, water-selective laser
- CDC/NIOSH Pocket Guide: Ethyl etherPhysical properties, incompatibilities and reactivities
REFERENCE FORMULA
Reference formula
Reference basis: 100 g
| Ingredient | Source quantity | Scaled quantity |
|---|---|---|
| Collodion cotton | 5 g | — |
| Ethanol 96% v/v | 20 g | — |
| Ether | 75 g | — |
Prerequisite formulations
No separate prerequisite monograph is listed.
Documentation
Preparation description
Colourless or slightly opalescent viscous liquid with characteristic odour; highly flammable. [1]
Action and use
Collodion base; the source does not specify a therapeutic indication. [1]
Specifications
Pyroxylin: 5.0–6.0% w/w; ethanol: 17.5–21.0% w/w [1]
Light
Light exposure contributes to ether peroxide formation. [2]
Air and oxidation
Ether can form explosive peroxides on exposure to air/light. [2]
Water and solubility
No quantitative hydrolytic stability limit is given for this formula. Retain the prescribed water amount and quality. [1]
Humidity
No numerical relative-humidity limit is given for the finished product. Prevent raw-material wetting and condensation entering the container. [1]
Temperature
No permitted temperature excursion or freeze–thaw cycle is established. Processing and storage temperatures are stated in their respective fields. [1]
pH and compatibility
No finished-product pH range is specified. Do not add a pH adjuster without a supported formula change. [1]
Other interactions
Ethanol is incompatible with strong oxidants. [3]
Ingredient-specific information
Identity and weighing basis:
• Collodion cotton: 5 g.
• Ethanol 96% v/v: 20 g.
• Ether: 75 g.
The specified chemical forms/grades belong to the exact source formula. [1]
• Collodion cotton: 5 g.
• Ethanol 96% v/v: 20 g.
• Ether: 75 g.
The specified chemical forms/grades belong to the exact source formula. [1]
Staff protection
Risk assessment
Ethanol: flammable vapour; control ignition sources and provide suitable ventilation. Final classification depends on concentration/mixture.
Ether/collodion: flammable vapour and peroxide hazard; appropriate solvent, ventilation and ignition controls are required.
Reference batch: 100 g. First ingredient: Collodion cotton, 5 g. Independently check chemical form, units and every scale conversion before weighing.
As an intermediate, label identity and strength clearly and do not dispense as a finished medicine. Dilution or addition of an active requires new excipient, preservation and BUD calculations. Confirm release of every required base.
For the local assessment record quantity per preparation, work frequency, duration of open handling, potential exposure routes and effectiveness of controls. These are assessment inputs; no fictitious final risk score is assigned.
Volatile solvent in this formula: Ethanol 96% v/v 20 g; Ether 75 g. Exclude ignition sources and minimise vapours/open evaporation. Check ventilation, electrical equipment and container compatibility with the specific solvent.
Release checkpoint: confirm final volume or mass at the reference temperature, intended clarity or dispersion, and specified container/closure. Do not equate grams and millilitres without a justified density. [1], [2], [3], [4], [5], [9], [11]
Ether/collodion: flammable vapour and peroxide hazard; appropriate solvent, ventilation and ignition controls are required.
Reference batch: 100 g. First ingredient: Collodion cotton, 5 g. Independently check chemical form, units and every scale conversion before weighing.
As an intermediate, label identity and strength clearly and do not dispense as a finished medicine. Dilution or addition of an active requires new excipient, preservation and BUD calculations. Confirm release of every required base.
For the local assessment record quantity per preparation, work frequency, duration of open handling, potential exposure routes and effectiveness of controls. These are assessment inputs; no fictitious final risk score is assigned.
Volatile solvent in this formula: Ethanol 96% v/v 20 g; Ether 75 g. Exclude ignition sources and minimise vapours/open evaporation. Check ventilation, electrical equipment and container compatibility with the specific solvent.
Release checkpoint: confirm final volume or mass at the reference temperature, intended clarity or dispersion, and specified container/closure. Do not equate grams and millilitres without a justified density. [1], [2], [3], [4], [5], [9], [11]
Compounding conditions
BUD rationale
Final evidence decision: no product-specific study was found establishing a numerical BUD for this exact in-house formulation and container. Prefer the exact required pharmacopoeial material from an approved supplier, with an acceptable lot CoA, dating and after-opening instructions. Different pharmacopoeial formulas and methylated laboratory variants are not automatically interchangeable. In-house production requires a volatile-compatible aw assessment and written method/matrix safety suitability. Low aw does not establish solvent retention, chemical stability, seal integrity or peroxide control. No arbitrary 180-day period is assigned. This is a completed reference monograph, not certification of a released batch. This record does not specify a commercial pyroxylin grade or assay basis. Before any preparation, obtain evidence for dry-polymer content and the identity/amount of wetting agent, reconciled with the final specifications. Do not treat 5 g of unspecified wetted material as 5 g dry polymer or dry the material to correct the arithmetic. Same-session use does not remove this requirement. [1], [2], [13], [14]
Prerequisites
No separately registered base is required. Any commercial vehicle remains the exact named product in the formula table. [1]
Equipment
Balance with suitable minimum weight, mortar/pestle or homogeniser, mixing vessels, spatulas, thermometer for heated processes and volumetric equipment for mL quantities. [1]
Compounding method
Final evidence decision: no product-specific study was found establishing a numerical BUD for this exact in-house formulation and container. Prefer the exact required pharmacopoeial material from an approved supplier, with an acceptable lot CoA, dating and after-opening instructions. Different pharmacopoeial formulas and methylated laboratory variants are not automatically interchangeable. In-house production requires a volatile-compatible aw assessment and written method/matrix safety suitability. Low aw does not establish solvent retention, chemical stability, seal integrity or peroxide control. No arbitrary 180-day period is assigned. This is a completed reference monograph, not certification of a released batch. This record does not specify a commercial pyroxylin grade or assay basis. Before any preparation, obtain evidence for dry-polymer content and the identity/amount of wetting agent, reconciled with the final specifications. Do not treat 5 g of unspecified wetted material as 5 g dry polymer or dry the material to correct the arithmetic. Same-session use does not remove this requirement. [1], [2], [13], [14]
Observations
A specific fire and ether/nitrocellulose handling assessment is required.
Require a specific measurement or reliable published aw for this exact collodion with actual solvents and container documented. Check method suitability for volatile matrices; water content or dry residue is not aw. Do not transfer another collodion’s shelf life.
Laboratory aw is not compulsory for every preparation. Here the requirement remains specific to the complex volatile matrix and unverified category. Strong directly applicable published evidence may replace a new measurement; an instrument unsuitable for ether/ethanol cannot provide acceptable evidence. [1], [11], [12]
Require a specific measurement or reliable published aw for this exact collodion with actual solvents and container documented. Check method suitability for volatile matrices; water content or dry residue is not aw. Do not transfer another collodion’s shelf life.
Laboratory aw is not compulsory for every preparation. Here the requirement remains specific to the complex volatile matrix and unverified category. Strong directly applicable published evidence may replace a new measurement; an instrument unsuitable for ether/ethanol cannot provide acceptable evidence. [1], [11], [12]
Container and packaging
Airtight container, away from heat. [1]
Quality control
Pyroxylin: residue from 10.00 g evaporated at 30°C, 1.5–2.5 kPa, then desiccated to constant mass. Ethanol: Ph. Eur. 2.2.28 gas chromatography with acetone internal standard; full conditions in the source.
Record the method, acceptance criterion, actual result and reviewer separately in F-005. A critical specification failure requires quarantine and investigation under SOP-015; retesting needs justification. [1], [11]
Record the method, acceptance criterion, actual result and reviewer separately in F-005. A critical specification failure requires quarantine and investigation under SOP-015; retesting needs justification. [1], [11]
Storage
Dispensing
final_decision
Final evidence decision: no product-specific study was found establishing a numerical BUD for this exact in-house formulation and container. Prefer the exact required pharmacopoeial material from an approved supplier, with an acceptable lot CoA, dating and after-opening instructions. Different pharmacopoeial formulas and methylated laboratory variants are not automatically interchangeable. In-house production requires a volatile-compatible aw assessment and written method/matrix safety suitability. Low aw does not establish solvent retention, chemical stability, seal integrity or peroxide control. No arbitrary 180-day period is assigned. This is a completed reference monograph, not certification of a released batch. This record does not specify a commercial pyroxylin grade or assay basis. Before any preparation, obtain evidence for dry-polymer content and the identity/amount of wetting agent, reconciled with the final specifications. Do not treat 5 g of unspecified wetted material as 5 g dry polymer or dry the material to correct the arithmetic. Same-session use does not remove this requirement. [1], [2], [13], [14]
Independent Greek/English adaptation and organisation of facts from the cited source. This is not an official translation or publisher endorsement.
Sources and references
- Collodion (1994) (15/02/2012)1994PDF pp. 1–2master formula2026-10-14
- CDC/NIOSH — Pocket Guide to Chemical Hazards: Ethyl etherΔιαθέσιμο κείμενο / Retrieved textOfficial referenceraw material or occupational2026-09-10
- CDC/NIOSH — Pocket Guide to Chemical Hazards: Ethyl alcoholΔιαθέσιμο κείμενο / Retrieved textOfficial referenceraw material or occupational2026-09-10
- PN/L/PG/002/00 INDUMENTARIAΔιαθέσιμο κείμενο / Retrieved textPDF pp. 1–5general staff protection2026-09-10
- ASHP — USP <795> Key Changes2023pp. 1–3: scope, water activity and staff precautionsprofessional guidance; not the licensed USP chapter2026-09-12
- Texas State Board of Pharmacy — adopted 22 TAC §291.131, nonsterile compoundingTexas Register, 7 June 2024Beyond-use dating: aw categories, 14/35/90/180 days, limits and extensionspublic regulatory implementation of USP <795> BUD framework; not Greek law2026-09-12
- Illinois IDFPR — Nonsterile Compounding Self-Inspection ReportPublic checklist, retrieved 12 September 2026pp. 15–16, Establishing beyond-use datesPublic regulatory implementation of USP <795>; not Greek law; general limits and requirements for extension2026-09-12
- Allan MC, Mauer LJ. Dataset of water activity measurements of alcohol:water solutions using a Tunable Diode LaserData in Brief. 2017;12:364–369Table 1; ethanol/water at 25 °C; DOI 10.1016/j.dib.2017.04.017Full text read. Binary-mixture water activity; volume ratios before mixing, not finished medicinal-product shelf life2026-09-12
- NIOSH — Managing Hazardous Drug Exposures: Information for Healthcare Settings2023; DHHS (NIOSH) 2023-130Risk assessment; printed pp. 27–33, activity/formulation control tableWorkplace exposure, hierarchy of controls and activity-specific PPE; US government public-domain document2026-09-12
- USP — Compounding Standards and Beyond-Use Dates, 2022 updateNovember 2022, published by USP; public copy hosted by Mississippi Boardpp. 1–2; nonsterile tableRisk-based default categories; not product-specific stability or Greek law2026-09-12
- PIC/S — Guide to Good Practices for the Preparation of Medicinal Products in Healthcare EstablishmentsPE 010-4, 1 March 2014Chapters 1–9; Annex 2 (nonsterile liquids, creams, ointments)Professional quality-system framework; not automatic national legal adoption or certification2026-09-12
- FDA — Water Activity (aw) in FoodsInspection Technical Guide 39, 16 April 1984; website copy accessed 2026-09-12Definition; sorption behaviour; measurement equipmentMetrological principles only. Food regulatory thresholds and old instrument recommendations are not pharmaceutical BUD rules2026-09-12
- USP — General Chapter <795> FAQsUpdated 1 November 2023Questions 52, 54–56, 60–62; PDF pp. 11–14Primary clarification of aw classification, extension prerequisites and compounded-component BUDs; not automatic Greek legal adoption2026-10-14
- Addium/AQUALAB manufacturer: TDL2 volatile-sample water activity methodMeasurement principle, volatile samples, water-selective laserTargeted prerequisite / publication decision; not batch result2026-10-14