An ointment is a viscous semisolid preparation used topically on a variety of body surfaces. These include the
skinand the mucus membranes of the eye(an "eye ointment"), vagina, anus, and nose. An ointment may or may not be medicated.
The vehicle of an ointment is known as ointment base. The choice of a base depends upon the clinical indication for the ointment, and the different types of ointment bases are:
#Hydrocarbon bases. e.g. hard paraffin, soft paraffin.
#Absorption bases. e.g. wool fat, beewax.
#Water soluble bases. e.g. macrogols 200,300,400.
Properties which affect choice of an ointment base are:
#Ease of application and removal
Methods of preparation of ointments
Trituration: In this finely subdivided insoluble medicaments are evenly distributed by grinding with a small amount of the base followed by dilution with gradually increasing amounts of the base.
Fusion: In this method the ingredients are melted together in descending order of their melting points and stirred to ensure homogenity
Topical medication forms
(Source: [Doctor, why are you prescribing an ointment?;American Academy of Dermatology;http://www.skincarephysicians.com/eczemanet/doctor.html] )
* Cream - Emulsion of oil and water in approximately equal proportions. Penetrates
stratum corneumouter layer of skin well.
Ointment- Combines oil (80%) and water (20%). Effective barrier against moisture loss.
Gel- Liquefies upon contact with the skin.
* Paste - Combines three agents - oil, water, and powder; an ointment in which a powder is suspended.
* [http://www.rpsgb.org.uk/pdfs/mussheet06.pdf History of ointments]
Wikimedia Foundation. 2010.