Ointment

From Wikipedia, the free encyclopedia

An ointment is a viscous semisolid preparation used topically on a variety of body surfaces. These include the skin and the mucus membranes of the eye (an eye ointment), vagina, anus, and nose. An ointment may or may not be medicated.

Contents 1 Description 2 EVALUATION OF OINTMENTS 3 Methods of preparation of ointments 4 Topical medication forms 5 See also 6 External links

[edit] Description

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:

1. Hydrocarbon bases. e.g. hard paraffin, soft paraffin.
2. Absorption bases. e.g. wool fat, beewax.
3. Water soluble bases. e.g. macrogols 200,300,400.

The medicaments are dispersed in the base and later they get divided after the drug penetration into the living cells of skin.

[edit] EVALUATION OF OINTMENTS

1. Drug content 2. Release of medicament from base 3. Medicament penetration 4. Consistency of the preparation 5. Absorption of medicament into blood stream 6. Irritant effect.

Properties which affect choice of an ointment base are:

1. Stability
2. Penetrability
3. Solvent property
4. Irritant effects
5. Ease of application and removal

[edit] 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

[edit] Topical medication forms

(Source: ^[1])

• Cream - Emulsion of oil and water in approximately equal proportions. Penetrates stratum corneum outer 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.

• Powder

[edit] See also

• Cream (pharmaceutical)
• Lotion
• Liniment
• Gel

[edit] External links

• History of ointments

v • d • e Route of administration / Dosage forms Oral digestive tract: Tablet · Capsule · Orally disintegrating tablet · Elixir respiratory tract: Inhaler (Metered-dose, Dry powder) · Nebulizer Sublingual administration ENT Eye drop · Ear drop Transdermal Ointment · Cream · Transdermal patch · Lotion · Liniment · Gel · Shampoo Injection Subcutaneous · Intravenous · Intramuscular · Intrathecal Vaginal Pessary (vaginal suppository) · Vaginal ring · Douche · Intrauterine device Rectal Suppository · Enema