Calcium Hydroxide Solution

Liquid base or auxiliary solution: Calcium Hydroxide Solution. Additional appearance criteria are not established by the specific text reviewed. ^[1]

Base or auxiliary preparation for the technological use indicated by its title. Adding an active creates a new formula requiring separate compatibility and duration assessment. ^[1]

Ca(OH)2 ≥0.15% w/v ^[1]

Finished-product photostability is not specified. Any required container light protection is stated under Storage. ^[1]

No oxidative stability study of the finished mixture or inert-atmosphere requirement is provided. Use the source container. ^[1]

No quantitative hydrolytic stability limit is given for this formula. Retain the prescribed water amount and quality. ^[1]

No numerical relative-humidity limit is given for the finished product. Prevent raw-material wetting and condensation entering the container. ^[1]

No permitted temperature excursion or freeze–thaw cycle is established. Processing and storage temperatures are stated in their respective fields. ^[1]

No finished-product pH range is specified. Do not add a pH adjuster without a supported formula change. ^[1]

Calcium hydroxide: carbonates, phosphates, citrates and sulfates may cause precipitation. ^[2]

Identity and weighing basis:
• Calcium hydroxide: 10 g.
• Freshly boiled and cooled purified water: q.s. ad 1000 mL.
The specified chemical forms/grades belong to the exact source formula. ^[1]

Clean long-sleeved laboratory clothing, hair covering and gloves during handling; change gloves after contamination or damage.
Contain powder during weighing and trituration and use eye protection; select respiratory protection for the actual exposure. ^{[1], [3], [4]}

Reference batch: 1000 mL. First ingredient: Calcium hydroxide, 10 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.
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], [7], [9]}

Before mixing: verify each ingredient’s chemical form and lot, record theoretical amounts and check equipment cleanliness. Follow the temperatures and addition sequence in the procedure below. ^{[1], [4]}

No specific experimental period was located covering the complete exact formulation, container and microbiological suitability.
Selected conservative general rule: up to 14 days at 2–8 °C for an aqueous form without adequately established preservation. Refrigeration must not cause precipitation, irreversible separation or other loss of suitability. If that condition fails, do not apply 14 days at room temperature; obtain specific short-use evidence.
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], [6], [8], [10]}

No separately registered base is required. Any commercial vehicle remains the exact named product in the formula table. ^[1]

Balance with suitable minimum weight, mortar/pestle or homogeniser, mixing vessels, spatulas, thermometer for heated processes and volumetric equipment for mL quantities. ^[1]

Shake thoroughly and repeatedly. Allow to settle until clear. Siphon off the clear supernatant as required. ^[1]

The 10 g is an excess input, not a dissolved 1% product. Protect from CO2. ^[1]

Well-filled container. ^[1]

Titrate 25 mL with 0.1 M HCl using phenolphthalein R1. Each mL of titrant equals 3.705 mg Ca(OH)2.
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], [9]}

Source-reported conditions/container: Well-filled container.
For the selected general ceiling: 2–8 °C, provided physical suitability and compatibility with the specific source are maintained. The 14-day rule does not apply at room temperature. ^{[1], [5], [6]}

Intermediate base for compounding. Adding an active requires reassessment of the final composition, pH, preservation and BUD. ^[1]

Calcium Hydroxide Solution
Compounding base — not for direct administration
Quantity: ____ Batch: ____
Prepared: ____ Use by: ____
Patient / dose / frequency: ____
Storage: 2–8 °C, after confirming suitability for refrigeration.
Temperature for this batch BUD: ____ ^{[1], [5], [6]}

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.