Dear Colleagues, in this article, published by the American Pharmacists Association; I will share with you a formula used in the treatment of corticosteroid-responsive inflammatory and pruritic skin conditions.Formula
Dexamethasone 0.1% Topical Cream USPDexamethasone Sodium Phosphate USP…109 mg
(Equivalent to 100 mg Dexamethasone Phosphate)
Hydrophilic Ointment USP…………………….qs..100 gPreparationCalculate the required amount of each ingredient for preparation. Accurately weigh each ingredient. Dissolve dexamethasone sodium phosphate in a small amount of purified water. Add the solution into hydrophilic ointment USP and mix until homogeneous. Package and label.Use:Dexamethasone phosphate topical cream is indicated for the relief of inflammatory and pruritic manifestations of corticosteroid-responsive dermatoses.Packaging:Package in tight containers.Labeling:For external use only. Use only as directed.Stability: The preparation can be used for up to 6 months after compounding.Quality control:The actual yield is compared with the theoretical yield. Physical observation is performed.DiscussionDiscontinued and scarce drugs are not a new situation for pharmacy, but it is rapidly becoming a critical issue. There are many factors accompanying these shortages, but as a result, patients’ quality of life decreases and in some cases, they even face life-threatening situations.
Decadron®Phosphate Topical Cream is no longer commercially manufactured. It was withdrawn from the market by its manufacturer in 1995. However, this preparation is still prescribed by physicians and pharmacists continue to compound it. This formula is modifiable, and there are many excellent vehicles to choose from.
Decadron®Phosphate Topical Cream contains dexamethasone sodium phosphate (1.09 g) equivalent to 1 mg of dexamethasone phosphate in a greaseless thin layer base. Dexamethasone sodium equivalent to dexamethasone phosphate is calculated as follows: Dexamethasone USP (C22H29FO5) molecular weight is 392.47; dexamethasone sodium phosphate (C22H28FNa2O8P) USP molecular weight is 516.41. The molecular weight of dexamethasone phosphate (C22H30FO8P) is 472. Thus; 516.41 is divided by 472, yielding 1.094. That is, 1.094 mg of dexamethasone sodium phosphate is taken to equal 1 mg of dexamethasone phosphate.Dexamethasone sodium phosphate(C22H28FNa2O8P, molecular weight 516.41), is present as a white or yellowish, crystalline hygroscopic powder. It is odorless or has a faint odor of alcohol. It is freely soluble in water and very slightly soluble in alcohol. Dexamethasone sodium phosphate injection has a pH between 7 and 8.5.
Although not the identical vehicle used in previously existing commercial products, hydrophilic ointment USP is a greaseless, smooth vehicle suitable for many general applications. Hydrophilic ointment is a water-washable, oil-in-water emulsion vehicle containing methylparaben, propylparaben, sodium lauryl sulfate, propylene glycol, stearyl alcohol, white petrolatum, and purified water. It is miscible with water and aqueous solutions, and some amount of oily solution can be added to the internal phase of the emulsion.
Numerous other commercially available vehicles can make very good preparations, such as Dermabase, Lanaphilic, Unibase, Vanicream, and Velvachol. These vehicles can be selected based on physical appearance, aesthetic character, presence or absence of preservatives, and availability.Dermabase cream (Paddock Laboratories) is an odorless, washable oil-in-water emulsion cream base. It contains purified water (approx. 45%), mineral oil, petrolatum, cetostearyl alcohol, propylene glycol, sodium lauryl sulfate, isopropyl palmitate, imidazolidinyl urea, methylparaben, and propylparaben. It is a smooth, white, water-washable cream with a very slight pleasant odor; it is compatible with a wide variety of agents and is preserved.Lanaphilic(Medco), contains stearyl alcohol, white petrolatum, isopropyl palmitate, lanolin oil, propylene glycol, sorbitol, sodium lauryl sulfate, and parabens.Unibase(Warner Chilcott) is a non-greasy, water-removable base containing white petrolatum, glycerin, sodium lauryl sulfate, and propylparaben.Vanicream(Pharmaceutical Specialties) is an oil-in-water emulsion containing white petrolatum, cetostearyl alcohol, ceteareth 20, sorbitol solution, propylene glycol, simethicone, glyceryl monostearate, and polyethylene glycol monostearate. Free of dyes, fragrances, lanolin, parabens, and formaldehyde, it is a stable and widely compatible cream.Velvachol(Owen/Galderma) is a water-miscible vehicle containing petrolatum, mineral oil, stearyl alcohol, sodium lauryl sulfate, cholesterol, and parabens.
All of these vehicles are suitable and offer different preferable characteristics. They are easily removed with water, leaving little to no residue. They can be used as vehicles to incorporate aqueous solutions, and in some cases, purified or aromatic waters can be added to convert the cream into a lotion. Depending on the patient’s specific needs, colorants and fragrances can also be easily added.
Wishing you a good week…
Spec. Pharm. Ahmet Nezihi Pekcan
Pekcan Pharmacy – Konya
[email protected]
Tel: (332) 3520657http://www.majistralformul.com/
