Ointments active ingredient stability

The chemical stability of active ingredients incorporated into ointments or creams is frequently dependent on the namre of the ointment... 

The term pharmaceutical is used for chemicals that are produced for medical purposes. A pharmaceutical is typically composed of one or more active ingredients and many additional components (binder, stabilizers etc). The latter are present to provide a certain form of donation, for example, to integrate the active ingredient into a tablet, a powder, an ointment, or a solution. The active ingredients are produced using chemical synthesis, biological methods (such as fermentation or biocatalysis), or sequences of both. In addition, several active ingredients are obtained directly from plant extraction (e.g., morphine) or from chemical transformations of plant extracts (e.g., codeine). 

An ointment base is prepared by melting the ingredients together. Sterilisation can be performed by dry heating (see Sect. 30.5.2) or membrane filtration (see Sect. 30.6.1). Heat sterilisation requires a validated heat steriliser, which may be expensive. In addition, a disadvantage of dry heat sterilisation is the partial decomposition of the fat components. The degradation products could negatively influence the stability of the active substance and probably cause irritation of the eye. 

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