Tretinoin, Hydrocortisone and Hydroquinone Cream

General Notices

Note: Tretinoin, Hydrocortisone and Hydroquinone Cream is not currently licensed in the United Kingdom.

Action and use

Vitamin A analogue (retinoid) + corticosteroid + depigmenting agent.

Definition

Tretinoin, Hydrocortisone and Hydroquinone Cream contains Tretinoin, Hydrocortisone and Hydroquinone in a suitable basis.

The cream complies with the requirements stated under Topical Semi-solid Preparations, the requirements stated under Unlicensed Medicines and with the following requirements.

Content of tretinoin, C20H28O2

90.0 to 110.0% of the stated amount.

Content of hydrocortisone, C21H30O5

90.0 to 110.0% of the stated amount.

Content of hydroquinone, C6H6O2

90.0 to 110.0% of the stated amount.

Characteristics

A bright yellow cream.

Identification

A. Carry out the method for thin-layer chromatography, Appendix III A, using the following solutions in amber glassware and protected from light.
(1) Add 5 mL of methanol to a quantity of the cream containing 25 mg of Hydrocortisone. Shake, mix with the aid of ultrasound for 15 minutes and add sufficient methanol to produce 10 mL.
(2) 0.25% w/v of hydrocortisone BPCRS in methanol.
(3) 0.01% w/v of tretinoin BPCRS in methanol.
(4) 0.5% w/v of hydroquinone BPCRS in methanol.
chromatographic conditions
(a) Use as the coating silica gel (Merck silica gel 60 F254 plates are suitable).
(b) Use the mobile phase as described below.
(c) Apply 10 µL of each solution.
(d) Develop the plate to 15 cm.
(e) After removal of the plate, dry in air and examine under ultraviolet light (254 nm).
mobile phase

1.2 volumes of water, 8 volumes of methanol, 15 volumes of ether and 77 volumes of dichloromethane.

confirmation

The three principal spots in the chromatogram obtained with solution (1) correspond to those in the chromatograms obtained with solutions (2) to (4).

B. In the Assay for tretinoin, the retention time of the principal peak in the chromatogram obtained with solution (1) is similar to that of the principal peak in the chromatogram obtained with solution (2).
C. In the Assay for hydrocortisone, the retention time of the principal peak in the chromatogram obtained with solution (1) is similar to that of the principal peak in the chromatogram obtained with solution (2).
D. In the Assay for hydroquinone, the retention time of the principal peak in the chromatogram obtained with solution (1) is similar to that of the principal peak in the chromatogram obtained with solution (2).

Assay

For tretinoin

Carry out the method for liquid chromatography, Appendix III D, using the following solutions prepared immediately before use in amber glassware and protected from light.

(1) Shake a quantity of the cream containing 1 mg of Tretinoin with 100 mL of methanol until fully dispersed, add sufficient methanol to produce 250 mL and filter (a 0.45-µm nylon syringe filter is suitable).
(2) 0.0004% w/v of tretinoin BPCRS in methanol.
chromatographic conditions
(a) Use a stainless steel column (25 cm × 4.6 mm) packed with octadecylsilyl silica gel for chromatography (5 µm) (Spherisorb ODS1 is suitable) fitted with a stainless steel guard column (4 mm ×  3 mm) packed with the same material.
(b) Use isocratic elution and the mobile phase described below.
(c) Use a flow rate of 1 mL per minute.
(d) Use an ambient column temperature.
(e) Use a detection wavelength of 350 nm.
(f) Inject 20 µL of each solution.
mobile phase

0.1% w/v of tetramethylammonium hydrogen sulfate in a mixture of 1 volume of water and 9 volumes of methanol.

determination of content

Calculate the content of C20H28O2 in the cream using the declared content of C20H28O2 in tretinoin BPCRS.

For hydrocortisone

Carry out the method for liquid chromatography, Appendix III D, using the following solutions in amber glassware and protected from light.

(1) Shake a quantity of the cream containing 25 mg of Hydrocortisone in 150 mL of methanol, add sufficient methanol to produce 250 mL and filter (a 0.45-µm nylon syringe filter is suitable).
(2) 0.01% w/v of hydrocortisone BPCRS in methanol.
chromatographic conditions
(a) Use a stainless steel column (25 cm × 4.6 mm) packed with end-capped octadecylsilyl silica gel for chromatography (5 µm) (Spherisorb ODS2 is suitable) fitted with a stainless steel guard column (4 mm × 3 mm) packed with the same material.
(b) Use isocratic elution and the mobile phase described below.
(c) Use a flow rate of 1 mL per minute.
(d) Use an ambient column temperature.
(e) Use a detection wavelength of 238 nm.
(f) Inject 20 µL of each solution.
mobile phase

11 volumes of methanol, 35 volumes of acetonitrile and 54 volumes of a 0.1% w/v solution of orthophosphoric acid.

determination of content

Calculate the content of C21H30O5 in the cream using the declared content of C21H30O5 in hydrocortisone BPCRS.

For hydroquinone

Carry out the method for liquid chromatography, Appendix III D, using the following solutions in amber glassware and protected from light.

(1)  Shake a quantity of the cream containing 50 mg of Hydroquinone with 100 mL of methanol until fully dispersed, add sufficient methanol to produce 250 mL and filter (a 0.45-µm nylon syringe filter is suitable). Dilute 1 volume of the filtrate to 5 volumes with the mobile phase.
(2) 0.004% w/v of hydroquinone BPCRS in the mobile phase.
chromatographic conditions
(a) Use a stainless steel column (25 cm × 4.6 mm) packed with octadecylsilyl silica gel for chromatography (5 µm) (Spherisorb ODS1 is suitable) fitted with a stainless steel guard column (4 mm ×  3 mm) packed with the same material.
(b) Use isocratic elution and the mobile phase described below.
(c) Use a flow rate of 1 mL per minute.
(d) Use an ambient column temperature.
(e) Use a detection wavelength of 295 nm.
(f) Inject 20 µL of each solution.
mobile phase

1 volume of water and 9 volumes of methanol.

determination of content

Calculate the content of C6H6O2 in the cream using the declared content of C6H6O2 in hydroquinone BPCRS.

Storage

Tretinoin, Hydrocortisone and Hydroquinone Cream should be protected from light.