REFERENCE FORMULA
Reference formula
Reference basis: 100 g
| Ingredient | Source quantity | Scaled quantity |
|---|---|---|
| Minoxidil base | 2 g | — |
| Propylene glycol | 10 g | — |
| Purified water | 20 g | — |
| Ethanol 96% v/v | 68 g | — |
REFERENCE FORMULA SCALING
Proportional quantities of the same formula
Arithmetic aid. It does not change strength, dose, method or BUD and does not authorise compounding.
Theoretical calculation sheet
CGR-ES-016 · Minoxidil cutaneous solution 2% w/w AEMPS
Not an approved master record or batch release. BUD is not calculated.
| Ingredient | Reference | Calculated | Lot | Actual quantity |
|---|
Prerequisite formulations
No separate prerequisite monograph is listed.
Documentation
Preparation description
Clear, colourless solution. [1]
Action and use
Topical minoxidil for alopecia according to the source. [1]
Specifications
Clear, colourless solution. [1]
Light
Finished-product photostability is not specified. Any required container light protection is stated under Storage. [1]
Air and oxidation
No oxidative stability study of the finished mixture or inert-atmosphere requirement is provided. Use the source container. [1]
Water and solubility
Propylene Glycol: JP classifies the corresponding pure raw material as miscible in water. [5]
Humidity
Temperature
For the finished product the source specifies:
100 mL amber metered bottle, tightly closed, <25 °C. [1]
100 mL amber metered bottle, tightly closed, <25 °C. [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. [2]
Ingredient-specific information
Propylene glycol (1,2-propanediol): colourless viscous water-miscible cosolvent and humectant. A small amount does not establish adequate preservation.
Propylene Glycol: raw-material water solubility is classified as miscible by JP.
Propylene glycol: retain original manufacturer, lot and reliable certificate. For the applicable raw materials, FDA describes DEG and EG testing, each limited to 0.10% under the relevant monograph. This is a raw-material limit. [4], [5], [6]
Propylene Glycol: raw-material water solubility is classified as miscible by JP.
Propylene glycol: retain original manufacturer, lot and reliable certificate. For the applicable raw materials, FDA describes DEG and EG testing, each limited to 0.10% under the relevant monograph. This is a raw-material limit. [4], [5], [6]
Staff protection
Risk assessment
Ethanol: flammable vapour; control ignition sources and provide suitable ventilation. Final classification depends on concentration/mixture.
Propylene glycol: assess exposure from all medicines, especially in neonates, children under 5 and renal/hepatic impairment. For oral dosing: mg/kg/day = mg/mL × daily mL ÷ body weight in kg.
Reference batch: 100 g. First ingredient: Minoxidil base, 2 g. Independently check chemical form, units and every scale conversion before weighing.
Verify chemical form and the w/w, w/v or v/v concentration basis against the formula. Do not equate g and mL without supported density. Check clarity/crystallisation and exact application route.
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 68 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], [7], [10], [12]
Propylene glycol: assess exposure from all medicines, especially in neonates, children under 5 and renal/hepatic impairment. For oral dosing: mg/kg/day = mg/mL × daily mL ÷ body weight in kg.
Reference batch: 100 g. First ingredient: Minoxidil base, 2 g. Independently check chemical form, units and every scale conversion before weighing.
Verify chemical form and the w/w, w/v or v/v concentration basis against the formula. Do not equate g and mL without supported density. Check clarity/crystallisation and exact application route.
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 68 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], [7], [10], [12]
Compounding conditions
BUD rationale
Period reported by source: 3 months.
This duration is a specific formulary/source instruction. This review did not verify a complete primary study establishing chemical, physical and microbiological extension for the same finished formulation.
Selected general rule: up to 35 days for an aqueous form appropriately preserved in its final composition and pH. Use 20–25 °C, or 2–8 °C only where permitted/required by the source and compatible with the dosage form. A preservative name is insufficient if it is diluted, inactivated or partitioned into another phase.
The reference-policy ceiling in this edition is the shorter of the source period above and the general ceiling. Extension needs matching active/excipients/strength, container, temperature, a stability-indicating method and the required microbiological evidence for aqueous extension. An applicable official USP–NF compounded monograph is assessed separately in its complete text.
Use-by date = the earliest allowed date from preparation plus selected period, ingredient expiries and any shorter supported limit. In-use dating never extends overall BUD. Complete the actual date for the batch after the required checks.
A default is a conservative dating limit, not experimental proof of batch stability. Its category depends on final composition, preservation and permitted temperatures. Water percentage or loss on drying does not determine aw. Document using SOP-014/F-006; use SOP-017/F-012 for specific aw evidence.
USP clarification: aw measurement is not required for every nonsterile preparation. Category assignment may use the exact composition and relevant representative examples; an uncertain or borderline formulation is best assessed by a suitable specific measurement. This edition contains no measured aw or released batch. The final preparation generally must not outlast the remaining BUD of its compounded bases/intermediates. An exception requires specific justification that physical, chemical and microbiological quality is not adversely affected. Record the final limit, intermediate preparation dates and their actual expiry dates separately. [1], [8], [9], [11], [13]
This duration is a specific formulary/source instruction. This review did not verify a complete primary study establishing chemical, physical and microbiological extension for the same finished formulation.
Selected general rule: up to 35 days for an aqueous form appropriately preserved in its final composition and pH. Use 20–25 °C, or 2–8 °C only where permitted/required by the source and compatible with the dosage form. A preservative name is insufficient if it is diluted, inactivated or partitioned into another phase.
The reference-policy ceiling in this edition is the shorter of the source period above and the general ceiling. Extension needs matching active/excipients/strength, container, temperature, a stability-indicating method and the required microbiological evidence for aqueous extension. An applicable official USP–NF compounded monograph is assessed separately in its complete text.
Use-by date = the earliest allowed date from preparation plus selected period, ingredient expiries and any shorter supported limit. In-use dating never extends overall BUD. Complete the actual date for the batch after the required checks.
A default is a conservative dating limit, not experimental proof of batch stability. Its category depends on final composition, preservation and permitted temperatures. Water percentage or loss on drying does not determine aw. Document using SOP-014/F-006; use SOP-017/F-012 for specific aw evidence.
USP clarification: aw measurement is not required for every nonsterile preparation. Category assignment may use the exact composition and relevant representative examples; an uncertain or borderline formulation is best assessed by a suitable specific measurement. This edition contains no measured aw or released batch. The final preparation generally must not outlast the remaining BUD of its compounded bases/intermediates. An exception requires specific justification that physical, chemical and microbiological quality is not adversely affected. Record the final limit, intermediate preparation dates and their actual expiry dates separately. [1], [8], [9], [11], [13]
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
Mix propylene glycol and ethanol. Dissolve minoxidil and slowly add water with stirring. [1]
Observations
The 2024 revision gives all quantities in g. Do not label as 2% w/v. [1]
Container and packaging
100 mL amber metered bottle, tightly closed, <25 °C. [1]
Quality control
Clear, colourless solution.
Polyol incoming QC: pharmacies test each lot or ensure documented testing by a reliable supplier, as described by FDA. IR identity alone does not exclude DEG/EG.
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], [6], [12]
Polyol incoming QC: pharmacies test each lot or ensure documented testing by a reliable supplier, as described by FDA. IR identity alone does not exclude DEG/EG.
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], [6], [12]
Storage
100 mL amber metered bottle, tightly closed, <25 °C. [1]
Dispensing
Dispense with a clear route, strength and use-by date. Complete amount per application and frequency from the prescription. [1]
Labelling
Minoxidil cutaneous solution 2% w/w AEMPS
External use
Quantity: ____ Batch: ____
Prepared: ____ Use by: ____
Patient / dose / frequency: ____
Storage: 100 mL amber metered bottle, tightly closed, <25 °C.
Temperature for this batch BUD: ____ [1]
External use
Quantity: ____ Batch: ____
Prepared: ____ Use by: ____
Patient / dose / frequency: ____
Storage: 100 mL amber metered bottle, tightly closed, <25 °C.
Temperature for this batch BUD: ____ [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.
Independent Greek/English adaptation and organisation of facts from the cited source. This is not an official translation or publisher endorsement.
Sources and references
- FN/2006/PO/039 MINOXIDIL AL 2%, SOLUCIÓN DE. Modificado 20242006 / αναθ. 2024PDF pp. 1–4master formula2026-10-14
- 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
- EMA — Questions and answers on propylene glycol used as an excipient, EMA/CHMP/704195/20139 October 2017Sections 1–3 and annexingredient facts2026-09-12
- MHLW — Japanese Pharmacopoeia XVIII: Propylene GlycolJP XVIII, 2021; English textPrinted p. 1600; Description; Containers and storageraw-material monograph2026-09-12
- FDA — Testing of Glycerin, Propylene Glycol, Maltitol Solution, Hydrogenated Starch Hydrolysate, Sorbitol Solution, and Other High-Risk Drug Components for Diethylene Glycol and Ethylene GlycolMay 2023, revision 1Recommendations; section on pharmacy compoundingraw material quality2026-09-12
- 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
- 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
- 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