Dear Colleagues; I will present this cream, which we generally prefer to purchase ready-made in our pharmacies and which is an emulsion belonging to the group of bases capable of holding water, as the formula of the week.
Rp
Spermaceti …………………….. 125.00 g
White Beeswax ………………… 120.00 g
Liquid paraffin ………………….. 560.00 g
Borax ……………………………… 5.00 g
Distilled water ……………………. 190 ml
These types of creams are water-in-oil (w/o) type emulsion bases. When cold creams (cooling creams) are applied to the skin, the emulsion breaks down and provides a cooling sensation due to the evaporation of water. There are also cold creams that are oil-in-water (o/w) emulsions prepared with certain organic emulsifiers, but their sensory effect is greasy.
If we recall the definition of emulsion; emulsions are uniform-appearing, heterogeneous systems formed by dispersing one of two liquids that do not form a true solution into the other. The dispersed liquid forms the internal phase (dispersed phase) of the mixture, while the other forms the external phase (dispersion medium).
a) Emulsions where the external phase is water and the internal phase is oil. These are called oil-in-water (o/w) emulsions. Milk is such a natural emulsion.
b) Emulsions where the external phase is oil and the internal phase is water. These are called water-in-oil (w/o) emulsions. Lime liniment is such an emulsion.
c) Multiple emulsions. Water/oil/water emulsions. The influenza vaccine is prepared in the form of a multiple emulsion. Similar emulsions of insulin and methotrexate have also been successfully prepared.
If we examine the ingredients included in the formula;
Spermaceti-Spermaceti-Wallrath-Blanc de baleine T.P.; Obtained from the oil found in the cranial cavities of sperm whales. It contains cetyl esters of palmitic, lauric, and myristic acids. It turns yellow over time. Insoluble in water; soluble in alcohol, ether, oils, and carbon disulfide. It is included in the formulation of cold creams and some cosmetics.
White beeswax–Cera alba-Wax-Cera flava-Wachs-Cire T.P.; These are honeycombs made by bees. Its melting point is 62–66 °C. Insoluble in water. Partially soluble in alcohol and ether, completely soluble in fatty oils. White beeswax is obtained by bleaching yellow beeswax in the sun. It is used as a base for cerates as well as in the formulation of ointments and suppositories.
Liquid paraffin-Paraffinum liquidum-Paraffine liquide-Huile de vaseline T.P.; It is the fraction obtained between 345–375 °C during petroleum distillation. Immiscible with water. Insoluble in alcohol. Miscible with fixed oils (except castor oil). Internally administered as a laxative at doses of 15–40 g. It is not recommended to be used as a vehicle in cold and rhinitis medications.
Borax-Sodii boras-Tenkar-Borax-Borate de sodium T.P.; These are prismatic crystals. Soluble in 22 parts of water at 20 °C, 0.5 parts of boiling water, and glycerin; insoluble in alcohol. Incompatible with strong acids. In addition, it is used externally in creams as a mild astringent and emulsifier (this term, also called emulsifying agent, is used to mean lowering surface tension and facilitating blending). Used as a mild antiseptic in the form of gargles and mouthwashes in stomatitis, aphthae, and thrush (muguet), and its solution or ointment is used in some skin diseases (eczema, erythema).
Preparation: Spermaceti and white beeswax are cut into small pieces and placed in an evaporating dish. Liquid paraffin is added to it, melted in a water bath, and heated up to 70 °C. The borax, placed in a small beaker, is dissolved in distilled water and also heated in a water bath up to 70 °C; this warm solution is added to the previously melted mixture at the same temperature, first slowly and then by stirring rapidly. It is stirred continuously until it congeals and transferred into its container. It is labeled appropriately. If the beeswax is dirty, it is melted and filtered through a cloth before use.
Dear colleagues;
As you may recall, I started writing on 19/11/2012 under the title “Magistral formula pharmacies in the new era“, and I have decided to continue writing the articles that I had been publishing continuously every week by publishing once a month for a while instead. I hope you will understand. With my highest regards and respects…
Pharm. Ahmet Nezihi PEKCAN
Specialist Pharm. Ahmet Nezihi Pekcan
Pekcan Pharmacy – Konya
[email protected]
Tel: (332) 3520657
http://www.majistralformul.com/
