PHG111 Lecture 2 15102024 PDF

Function of a Pharmacognosist: 1.Identification of sources of drugs. 2.Determination of morphological characters. 3.Investigation of potency, purity and admixture. 4.Planning and devising of cultivation of medicinal plants. 5.Prescription of the detail processes of collection, drying and preserv...

Function of a Pharmacognosist: 1.Identification of sources of drugs. 2.Determination of morphological characters. 3.Investigation of potency, purity and admixture. 4.Planning and devising of cultivation of medicinal plants. 5.Prescription of the detail processes of collection, drying and preservation of drugs. 6.Knowledges of active constituents, their chemical nature and reactions. 10/15/2024 17 For detailed description of each individual drug, the following point are to be considered: 1. Origin: biological, geographical and commercial. 2. Cultivation, collection, drying, packing and storage. 3. Characters, sensory, morphology, histology and powders. 4. Constituents and uses in medicine. 5. Evaluation and testing for adulteration. 10/15/2024 18  Classification of Drugs for Study: Drugs are classified in different ways to make their study easy. The most important methods are: 1. Alphabetical: According to Latin or English names. 2. Taxonomical: According to plants from which the drugs are obtained in phyla, orders, families, genera and species. 10/15/2024 19 Plant Taxonomy 3. Morphological: According to plant organs e.g. leaves, flowers, fruits, seeds, herbs, roots, rhizomes, barks, woods, these are known as organized drugs, or as plant products; as dried latex, extracts, gums, resins, oils, fats, waxes etc. referred to as unorganized drugs. 4. Chemical: According to the major active constituents they contain, e.g. Drugs containing glycosides, alkaloids, bitter principles, tannins, volatile oils...etc.. 5. Pharmacological or Therapeutic: As astringents, irritants, drugs affecting: GIT, heart, kidney, nervous system...etc. 10/15/2024 21  OFFICIAL AND UNOFFICIAL DRUGS: An official drug is the one listed in a book recognized by the government health authority known as Pharmacopoeia. This book contains the official standards for each drug. 10/15/2024 22 UTILISATION OF DRUGS: Drugs are mainly used for treatment of diseases and as prophylactic. Nevertheless, there are many other uses of drugs summarized as follows: 1. Filtration materials: Cotton, kieselguhr (Diatomite). 2. Adsorbents: Charcoal. 3. Decolorizing agents: Charcoal. 10/15/2024 23 4. Suspending and Emulsifier: Acacia. 5. Solvents: Fixed oils of almond, corn, olive, cotton seed, castor, peanut, poppy seed, sesame...etc. 6. Ointment Bases: Wool fat, bees wax... 7. Suppositories Bases: Gelatin, cacao butter. 8. Gillies: Gelatin, pectin's, gums...etc. 10/15/2024 24