or product development purposes.

3. Responsibilities

• Stability Analyst: Prepares and exposes samples under defined conditions.
• Quality Control (QC): Performs analysis of photostressed samples.
• Quality Assurance (QA): Reviews and approves the test plan and outcome.
• R&D/Formulation Development: Evaluates the formulation impact in case of degradation.

4. Accountability

Head – Quality Assurance is accountable for ensuring compliance with regulatory guidelines and proper execution of photostability testing procedures.

5. Procedure

5.1 Preparation

1. Obtain representative samples of the gel product in its market pack and container-closure system.
2. Label each sample clearly with batch number, exposure date, and time.
3. Place the control (dark) sample and exposed sample in different containers for comparison.

5.2 Exposure Conditions

1. Use a validated photostability chamber that complies with ICH Q1B Option 2 (fluorescent and near UV lamps).
2. Ensure exposure to a minimum of 1.2 million lux hours and 200 watt-hours/m² of near UV energy.
3. Maintain chamber temperature between 25°C to 30°C.

5.3 Sample Placement

1. Place exposed samples evenly on a rotating platform within the chamber to ensure uniform exposure.
2. Wrap the control samples in aluminum foil or place in a light-opaque container.

5.4 Duration and Monitoring

1. Expose samples for a period sufficient to reach the specified lux and UV exposure levels.
2. Monitor and document lux and UV levels using calibrated sensors at set intervals.

5.5 Evaluation of Samples

1. After exposure, retrieve the samples and store at ambient conditions until analysis.
2. Perform visual inspection for discoloration, phase separation, and turbidity.
3. Conduct chemical tests for assay, degradation products, pH, and viscosity using validated methods.

5.6 Documentation and Reporting

1. Document all test data in the Photostability Testing Log (Annexure-1).
2. Prepare the Photostability Test Summary Report (Annexure-2).
3. Submit findings to QA for review and sign-off.

6. Abbreviations

• QA: Quality Assurance
• QC: Quality Control
• ICH: International Council for Harmonisation
• UV: Ultraviolet
• Lux: Unit of illumination

7. Documents

1. Photostability Protocol – Annexure-1
2. Photostability Summary Report – Annexure-2
3. Chamber Qualification Record

8. References

• ICH Q1B: Photostability Testing of New Drug Substances and Products
• WHO Technical Report Series No. 1010
• PharmaSOP – Stability Testing SOP

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation	Jr. Production Chemist	QA Executive	Head – Manufacturing
Department	Gel Manufacturing	Quality Assurance	Manufacturing

11. Annexures

Annexure-1: Photostability Testing Log

Batch No.
Exposure Start Date
Exposure End Date
Exposure Conditions	Lux: __________ | UV: __________
Temperature (°C)
Visual Appearance
Remarks

Annexure-2: Photostability Test Summary Report

Test Parameter	Initial Result	Post-Exposure Result	Limit	Conclusion
Assay (%)
Degradation Products (%)
pH
Viscosity (cP)

Revision History

Revision Date	Revision No.	Change Description	Reason	Approved By
16/05/2022	1.0	Initial Issue	New SOP	QA Head
02/06/2025	2.0	Aligned with ICH Q1B Option 2 and added annexures	Regulatory Compliance	QA Head