Standard Operating Procedure for Osmolarity Testing for Chewable and Dispersible Tablets

Department	Quality Control
SOP No.	SOP/TAB/114/2025
Supersedes	SOP/TAB/114/2022
Page No.	Page 1 of 6
Issue Date	01/03/2026
Effective Date	06/03/2026
Review Date	01/03/2027

1. Purpose

To define the procedure for performing osmolarity testing for chewable and dispersible tablets, ensuring that the osmolarity of the formulation meets the required standards for oral administration.

2. Scope

This SOP applies to the testing of osmolarity in chewable and dispersible tablets to ensure the product’s dissolution and absorption are optimized for patient safety and efficacy.

3. Responsibilities

• Quality Control (QC): Responsible for conducting osmolarity testing and ensuring that the results comply with specifications.
• Quality Assurance (QA): Ensures that the testing is performed according to the SOP and reviews the results to ensure compliance with regulatory requirements.
• Laboratory Personnel: Responsible for performing osmolarity testing according to the specified procedures and ensuring accurate documentation of the results.

4. Accountability

The QC Manager is accountable for ensuring that osmolarity testing is performed accurately and that the results meet the required specifications. The QA Manager is responsible for reviewing and approving the results to ensure regulatory compliance.

5. Procedure

5.1 Sample Preparation

1. Weigh an appropriate number of chewable or dispersible tablets (usually 10 tablets) for osmolarity testing.
2. Place the tablets into a clean container and add a specific volume of distilled water (e.g., 100 mL) to dissolve the tablets.
3. Ensure that the tablets are fully dissolved or dispersed in the solution, depending on the formulation requirements.
4. For chewable tablets, ensure the tablets are chewed or broken into smaller pieces before dissolution to simulate oral administration.

5.2 Performing Osmolarity Measurement

1. Use a calibrated osmometer to measure the osmolarity of the prepared solution.
2. Follow the instrument’s operating manual to ensure correct procedure, ensuring that the osmometer is set to measure in the correct unit (osmoles per liter, Osm/L).
3. Insert the sample into the osmometer and record the osmolarity value displayed on the device.
4. Repeat the measurement at least three times for consistency and calculate the average osmolarity.

5.3 Data Analysis

1. Calculate the average osmolarity from the repeated tests.
2. Compare the measured osmolarity against the predefined specifications for chewable or dispersible tablets, typically between 200–500 mOsm/L depending on the formulation.
3. Ensure that the osmolarity of the tablet solution falls within the acceptable limits. If the osmolarity is outside the specified range, perform a root cause analysis and document findings in the deviation report (Annexure-1).

5.4 Acceptance Criteria

1. The osmolarity of the tablet solution should fall within the specified range (typically 200–500 mOsm/L, depending on the formulation). If the osmolarity is outside this range, the batch must be investigated and appropriate corrective actions should be taken.
2. If the osmolarity does not meet the acceptance criteria, initiate an investigation to determine the root cause, which may include formulation, manufacturing processes, or testing errors.

5.5 Documentation and Record-Keeping

1. Document the osmolarity test results, including the individual measurements, average osmolarity, and any deviations from the expected range in the batch record (Annexure-2).
2. Ensure all records are signed, dated, and stored according to the company’s record retention policy for future audits and inspections.
3. Maintain raw data, including osmometer calibration records and any deviation reports, for regulatory compliance and future reference.

5.6 Post-Test Actions

1. Clean and calibrate the osmometer as per the manufacturer’s recommendations after each use to ensure accurate future testing.
2. Dispose of used samples and solvents according to the company’s waste disposal procedures.
3. Ensure that all equipment used for osmolarity testing is maintained and regularly serviced according to the manufacturer’s guidelines and company SOPs.

6. Abbreviations

• SOP: Standard Operating Procedure
• GMP: Good Manufacturing Practice
• QC: Quality Control
• QA: Quality Assurance
• mOsm/L: Milliosmoles per Liter
• API: Active Pharmaceutical Ingredient

7. Documents

1. Batch Record (Annexure-2)
2. Deviation Report (Annexure-1)

8. References

• USP <831> – Osmolarity
• 21 CFR Part 211 – Current Good Manufacturing Practice for Finished Pharmaceuticals (US FDA)
• European Pharmacopoeia (EP) – Specifications for Osmolarity Testing

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Deviation Report

Deviation Date	Batch Number	Deviation Description	Corrective Action	Responsible Person
15/12/2025	Batch 001	Osmolarity outside specified range	Reformulated and re-tested	John Doe

Annexure-2: Batch Record

Batch Number	Sample Weight (g)	Osmolarity (mOsm/L)	Result
Batch 001	100 g	350 mOsm/L	Pass

Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By
01/01/2024	1.0	Initial Version	New SOP Creation	QA Head
01/02/2025	2.0	Updated Acceptance Criteria	Improved osmolarity control	QA Head