GALENICALS

					GALENICALS
OBJECTIVE: DEFINE GALENICALS TERMS THAT COMES UNDER GALENICALS DISTINGISH BETWEEN THE DIFFERENT PROCESSES. USES OF THE PROCESS.

GALENICALS








GALENICAL Galenicals are pharmaceutical preparations obtained by macerating or percolating drugs with alcohol of appropriate strength, or some menstrum carefully selected to remove as thoroughly the desired principle and to leave the inert and other undesirable constituents of the plant undissolved. The preparations include under the galenicals are infusions ,decoctions, fluid extracts and fluid glycerities, vinegars, and tinctures. It was Galen a Greek pharmacist of Rome (131-200 AD) who described various methods of extracting the crude drugs for the first time and hence the branch dealing with the extraction of plant and animals drug is known as Galenical pharmacy and the product as Galenicals

GALENICALS




Extraction as the term is used in pharmaceutically, involves the separation of medicinally active portion of plant or animal tissues form the inactive or inert components by using selective solvents in standered extraction procedures. The products obtained form plants are relatively impure liquids semisolids or powdered intended only for oral or external use. These include classes of preparations known as decoctions, infusion, fluidextracts. Tinctures pilular (semisolid) extracts, and powered extracts, such preparation popularly have been called galenicals, after galen, the 2nd century Greek physician.

GALENICALS






EXTRACTION: Extraction of digital glycosides has been carried out using super critical carbon dioxide. Other techniques include ultrasonic, rotary film evaporators, hydro distillation, liquid chromatography , multiple solvent extraction, countercurrent extraction, and gravitation dynamics. The principal methods of extraction are maceration, percolation, digestion, infusion, and decoction. The quality of the finished product can be enhanced by standardizing primary extracts and carrying out analytical assays during production on the raw materials, intermediate products, and manufacturing procedures. The processes of particular importance , insofar as the USP concerned are those of maceration and percolation as described specifically for belladonna Extract USP and cascara Sagrada Extract USP.

GALENICALS


INFUSION(INFUSA): An infusion is a dilute solution of the readily soluble constituents of crude drugs. Fresh infusions are prepared by macerating the solids for a short period of time with either cold or boiling water. The USP has not included infusions for some time.

GALENICALS


 1.

2. 3. 4.

Time: prepared by macerating the drug in water for short period of time. varying from 15 min to 2 hrs. Volume of product: depend on quantity of menstruum retained by the marc ,which should not be pressed. The temperature The degree of comminution of drug The length of maceration (nature of drug and constituent to be extracted)

GALENICALS





 



Prepared in earthen ware vessel. Special infusion apparatus included ALSOP’S INFUSION JAR,SQUIRE INFUSION MUG. The drug is suspended or enclosed in muslin (tea bag). Stirring done when drug settles down. In case of hot water being added ,vessel should be weighed and tare d and warmed. Infusion should be freshly prepared and dispensed within 12 hrs of preparation.

GALENICALS



Concentrated Infusions
These differ from the infusions in the respect that they either use alcohol as a menstruum as alcohol is used as a preservative. They are prepared by methods of maceration similar to the tinctures. THE BP &BPC recommends the use of concentrated infusion from which infusion can be prepared by diluting one volume of conc.infusion to 10 vol by water. Eg, includes, orange peel infusion conc. BPC. & conc. compound gentian infusion BP. (double maceration)







GALENICALS


DECOCTION(DECOCTA): This once process extracts water soluble and heat stable constituents form crude drugs by boiling in water for 15 min, cooling, straining and passing sufficient cold water through the procedure the required volume.

GALENICALS










Process is used when active drug principle is heat stable. Incase of addition of number of ingredients ,hard ligneous drug added first with addition of aromatic or volatile oil near the end of the process. If decoction is followed by evaporation then a solid or semi solid extract is produced. Aqueous product –susceptible to decomposition-freshly prepared Fell from use in early 1950 last official formulae e.g., appeared in BPC1949.

GALENICALS




DIGESTION: This is the form of maceration in which gentle heat is used during the process of extraction. It is used when moderately elevated temperatures are not objectionable and the solvent efficiency of the menstruum is increased thereby.

GALENICALS




OXYMELS: Term applied to purified honey to which acetic acid has been added. E.G, squill oxymel BPC1973, Oxymel BPC1973,

GALENICALS

 



  

VINEGARS (aceta): Used as a menstruum for preparing medicinal preparation. Antiseptic Mediccated vinegars: solution of drug in dilute acetic acid,w/c is a good solvent & possess Antiseptic properties Wine &cider vinegars are also used Squill vinegar BPC. (UK ONLY OFFICIAL PREP) Also used treat pseudomonas aeroginosa infection in wounds in burn unit.

GALENICALS








EXTRACTS: Extracts are defined in the USP as concentrated preparation o vegetables or animal drugs obtained by removal of the active constituents of the respective drugs with suitable menstrual evaporation of all or nearly all of the solvent, and adjustment of the residual masses or powders to the prescribed standards. There are three forms of extracts semi liquids or liquids of syrupy consistency, plastic masses (known as pilular or solid extracts) and dry powders (known as powdered extracts). Most extracts are prepared by extracting the drug by percolation. The percolate is concentrated, generally by distillation under reduced pressure. The use of heat is avoided where possible because of potential injurious effects on active constituents. Powdered extracts that are made from drugs that contain inactive oily or fatty matter may have to be defatted or prepared form defatted drug.

GALENICALS


   1.





Produced by action of various solvent. Eg., Aq, alcoholic, ethereal, acetic or ammoniated) using a variety of processes (expression, maceration, decoction, percolation). Followed by evaporation with or with out vacuum assistance to produce liquid ,semi solid or solid product. Minimize the amount o inert matter present. Higher quantity of active principle than equivalent infusion, decoction or tinctures. Solid extract classified on basis of consistency: Soft extracts: semi sticky masses formed by conc of liq extract. consistency that of pill mass & paste. Not in use (difficulty to standardize the degree of softness) On storage the get hardened so difficult to handle.



Pure Glycyrrhiza Extracts USP

GALENICALS
2.
   


3. 

Dry extract: Easy to standardize Easy to handle Varied less in strength Storage do effect them when in powder form (absorb moisture & become a solid block) preferred form is granular. Belladonna Extracts USP Liquid extract: Used in extemporaneous compounding. E.g, liquorice extract BP.

GALENICALS


FLUIDEXTRACTS. The USP defines fluidextracts as being liquid preparation of vegetables drugs, containing alcohol as a solvent or as a preservative or both so made that unless otherwise specified in an individual monograph, each milliliter contains the therapeutic of 1g of the standard drug that it represent



  
 

There are five processes for the preparation of fluid extracts. Process A Process B Process C Process D Process E

GALENICAL


TINCTURES: Tinctures are defined in the USP as being alcoholic or hydro alcoholic solutions prepared from vegetables materials or from chemical substances. And example of the latter being Iodine Tincture. The USP specifically describes two general processes for preparing tinctures, one by percolation and the other by maceration. Percolation includes a modification so that tinctures that require assay for adjustment to specified potency thus may be tested before dilution to final volume.


				
DOCUMENT INFO
Shared By:
Tags:
Stats:
views:4376
posted:8/17/2009
language:English
pages:19
Description: this lecture prepared from dow university of health sciences, dow college of pharmacy.