Cream (pharmaceutical)
Encyclopedia
A cream is a topical preparation usually for application to the skin
Skin
-Dermis:The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many Mechanoreceptors that provide the sense of touch and heat...

. Creams for application to mucus membranes such as those of the rectum
Rectum
The rectum is the final straight portion of the large intestine in some mammals, and the gut in others, terminating in the anus. The human rectum is about 12 cm long...

 or vagina
Vagina
The vagina is a fibromuscular tubular tract leading from the uterus to the exterior of the body in female placental mammals and marsupials, or to the cloaca in female birds, monotremes, and some reptiles. Female insects and other invertebrates also have a vagina, which is the terminal part of the...

 are also used. Creams may be considered pharmaceutical
Pharmaceutics
Pharmaceutics is the discipline of pharmacy that deals with all facets of the process of turning a new chemical entity into a medication able to be safely and effectively used by patients in the community. Pharmaceutics is the science of dosage form design...

 products as even cosmetic creams are based on techniques developed by pharmacy
Pharmacy
Pharmacy is the health profession that links the health sciences with the chemical sciences and it is charged with ensuring the safe and effective use of pharmaceutical drugs...

 and unmedicated creams are highly used in a variety of skin conditions (dermatoses). The use of the Finger tip unit
Finger tip unit
In medicine, a finger tip unit is defined as the amount of ointment, cream or other semi-solid dosage form expressed from a tube with a 5mm diameter nozzle, applied from the distal skin-crease to the tip of the index finger of an adult. One FTU is enough to treat an area of skin twice the size...

 concept may be helpful in guiding how much topical cream is required to cover different areas.

Creams are semi-solid emulsion
Emulsion
An emulsion is a mixture of two or more liquids that are normally immiscible . Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms colloid and emulsion are sometimes used interchangeably, emulsion is used when both the dispersed and the...

s, that is mixtures of oil and water. They are divided into two types: oil-in-water (O/W) creams which are composed of small droplets of oil dispersed in a continuous phase, and water-in-oil (W/O) creams which are composed of small droplets of water dispersed in a continuous oily phase. Oil-in-water creams are more comfortable and cosmetically acceptable as they are less greasy and more easily washed off using water. Water-in-oil creams are more difficult to handle but many drug
Medication
A pharmaceutical drug, also referred to as medicine, medication or medicament, can be loosely defined as any chemical substance intended for use in the medical diagnosis, cure, treatment, or prevention of disease.- Classification :...

s which are incorporated into creams are hydrophobic and will be released more readily from a water-in-oil cream than an oil-in-water cream. Water-in-oil creams are also more moisturising as they provide an oily barrier which reduces water loss from the stratum corneum
Stratum corneum
The stratum corneum is the outermost layer of the epidermis, consisting of dead cells that lack nuclei and organelles. The purpose of the stratum corneum is to form a barrier to protect underlying tissue from infection, dehydration, chemicals and mechanical stress...

, the outermost layer of the skin.

Uses of creams

  • The provision of a barrier to protect the skin
    • This may be a physical barrier or a chemical barrier as with sunscreen
      Sunscreen
      Sunblock is a lotion, spray, gel or other topical product that absorbs or reflects some of the sun's ultraviolet radiation on the skin exposed to sunlight and thus helps protect against sunburn...

      s
  • To aid in the retention of moisture (especially water-in-oil creams)
  • Cleansing
  • Emollient effects
  • As a vehicle for drug substances such as local anaesthetics, anti-inflammatories
    Anti-inflammatory
    Anti-inflammatory refers to the property of a substance or treatment that reduces inflammation. Anti-inflammatory drugs make up about half of analgesics, remedying pain by reducing inflammation as opposed to opioids, which affect the central nervous system....

     (NSAIDs or corticosteroid
    Corticosteroid
    Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex. Corticosteroids are involved in a wide range of physiologic systems such as stress response, immune response and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte...

    s), hormone
    Hormone
    A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...

    s, antibiotic
    Antibiotic
    An antibacterial is a compound or substance that kills or slows down the growth of bacteria.The term is often used synonymously with the term antibiotic; today, however, with increased knowledge of the causative agents of various infectious diseases, antibiotic has come to denote a broader range of...

    s, antifungals or counter-irritants.


Creams are semisolid dosage forms containing one or more drug substances dissolved or dispersed in a suitable base. This term has traditionally been applied to semisolids that possess a relatively fluid consistency formulated as either water-in-oil (e.g., Cold Cream) or oil-in-water (e.g., Fluocinolone Acetonide Cream) emulsions. However, more recently the term has been restricted to products consisting of oil-in-water emulsions or aqueous microcrystalline dispersions of long-chain fatty acids or alcohols that are water washable and more cosmetically and aesthetically acceptable. Creams can be used for administering drugs via the vaginal route (e.g., Triple Sulfa Vaginal Cream). Creams are used to help sun burns

Composition:
There are four main ingredients of the cold cream
1: Water
2: Oil
3: Emulsifier
4: Thickening agent

Topical medication forms

(Source:)
  • Cream - Emulsion of oil and water in approximately equal proportions. Penetrates stratum corneum
    Stratum corneum
    The stratum corneum is the outermost layer of the epidermis, consisting of dead cells that lack nuclei and organelles. The purpose of the stratum corneum is to form a barrier to protect underlying tissue from infection, dehydration, chemicals and mechanical stress...

     outer layer of skin well.
    • Cold cream
      Cold cream
      Cold cream is an emulsion of water and certain fats, usually including beeswax and various scent agents, designed to smooth skin and remove makeup. The name derives from the cooling feeling that the cream leaves on the skin...

      s
  • Ointment - Combines oil (80%) and water (20%). Effective barrier against moisture loss.
  • Gel
    Gel
    A gel is a solid, jelly-like material that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state...

     - Liquefies upon contact with the skin.
  • Paste
    Paste (rheology)
    In physics, a paste is a substance that behaves as a solid until a sufficiently large load or stress is applied, at which point it flows like a fluid. In rheological terms, a paste is an example of a Bingham plastic fluid....

     - Combines three agents - oil, water, and powder; an ointment in which a powder is suspended.
  • Powder
  • Liniment
    Liniment
    Liniment , from the Latin linere, to anoint, is a medicated topical preparation for application to the skin. Preparations of this type are also called balm...

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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