2. SOURCES OF DRUGS
1) NATURAL
a) Plants
Oldest source of drugs used empiricallyOldest source of drugs used empirically
Leaves, seeds, flowers, roots, bark etcLeaves, seeds, flowers, roots, bark etc
Problems:
Identification of plantIdentification of plant
Climatic and social conditions of areaClimatic and social conditions of area
Season of collectionSeason of collection
Condition of storageCondition of storage
cont.
3. • Standardization of active principleStandardization of active principle
• Purity of active ingredientPurity of active ingredient
• Maintenance of supply lineMaintenance of supply line
• Active principle is synthesized after detectionActive principle is synthesized after detection
e.g.e.g. morphine, codeine, digitalis, quinine, atropine,morphine, codeine, digitalis, quinine, atropine,
reserpine and pilocarpinereserpine and pilocarpine
4. VARIOUS FORMS OF PLANT DRUG
• Extract, infusions, decoction, powders etcExtract, infusions, decoction, powders etc
• ChemicalsChemicals (alkaloids, glycosides, oil, resins,(alkaloids, glycosides, oil, resins,
tannins, gums etc.)tannins, gums etc.) isolated from different formsisolated from different forms
are used for humans and animals, c/d activeare used for humans and animals, c/d active
principlesprinciples
5. b) Animals
• Modern drugsModern drugs
• Active principles are proteins, oil and fats,Active principles are proteins, oil and fats,
enzymes and hormonesenzymes and hormones
• e.g. gonadotropins, heparin, insulin, thyroide.g. gonadotropins, heparin, insulin, thyroid
extract and enzymesextract and enzymes
6. c) Microorganisms
• Antibiotics derived = fungi and bacteria afterAntibiotics derived = fungi and bacteria after
discovery of penicillin in 1928 and its use indiscovery of penicillin in 1928 and its use in
19401940
• Use for infective diseasesUse for infective diseases
• E.g. penicillin, streptomycin, tetracycline,E.g. penicillin, streptomycin, tetracycline,
chloramphenicol and erythromycinchloramphenicol and erythromycin
7. d) Minerals
• Metals, metalloids, non-metal subs. and theirMetals, metalloids, non-metal subs. and their
compoundscompounds
• E.g. iron, calcium, magnesium, aluminium,E.g. iron, calcium, magnesium, aluminium,
sodium, potassium, sulphur, lithium etcsodium, potassium, sulphur, lithium etc
8. 2) SEMI-SYNTHETIC
• Complex moleculesComplex molecules
• Expensive and for impure natural compoundExpensive and for impure natural compound
• E.g. 6-aminopencillanic acid (fungus), semi-E.g. 6-aminopencillanic acid (fungus), semi-
synthetic human insulin (pork insulin)synthetic human insulin (pork insulin)
9. 4) SYNTHETIC
• Pharmaceutical laboratoryPharmaceutical laboratory
• Organic or inorganic or combination ofOrganic or inorganic or combination of
organic and inorganic compoundsorganic and inorganic compounds
• >90% drugs>90% drugs
• E.g. older drug; chloroform, ether, nitrousE.g. older drug; chloroform, ether, nitrous
oxide, chloral hydrateoxide, chloral hydrate
• Antipyretics, sulphonamides, antihistamines,Antipyretics, sulphonamides, antihistamines,
anticonvulsants, anti anxiety etcanticonvulsants, anti anxiety etc
10. RECOMBINANT DNA
TECHNOLOGY
• Human insulin human proinsulin geneHuman insulin human proinsulin gene
cDNA E.coli treat proinsulin to form insulincDNA E.coli treat proinsulin to form insulin
• Growth hormone, tissue plasminogenGrowth hormone, tissue plasminogen
activator, vaccines, interferon, erythropoitins,activator, vaccines, interferon, erythropoitins,
G-colony stimulating factorG-colony stimulating factor
11. Naming of Drugs (Nomenclature)
•A marketed drug has three names: a chemical name, a
generic name, and a brand name.
•A chemical name is given when a new chemical entity
(NCE) is developed.
12. • The chemical name is a scientific name based on the
compound's chemical structure (e.g., 6-thioguanine)
and is almost never used to identify the drug in a
clinical or marketing situation.
• The generic name does not belong to the company that
discovers the drug (or owns the patent). Once the
patent lifetime is expired, any company may market
the drug under the generic name.
13. Pharmacopoeias and Formularies
• The books containing the standards for drugs and other related
substances are known as pharmacopoeias and formularies.
• The pharmacopoeias contain a list of drugs and other related
substance regarding their source, descriptions, tests, formulas
for preparing the same, action and uses, doses, storage
conditions etc.
• Pharmacopoeias however, do not cover the entire field of
therapeutics and some countries have found it necessary to
supplement the pharmacopoeia with a more comprehensive
formulary or codex.
• These books are prepared under the authority of the
government of the respective countries. These books are
revised from time to time as to introduce the latest information
available as early as possible after they become established.
14. • Classification: The drug compendia are classified as :
Official compendia & Non-official compendia
• Official compendia are the compilation of drugs and other
related substances which are recognized as legal standards
of purity, quality and strength by government agency of
respective countries of their origin. Official compendia
include a) British Pharmacopoeia b) British Pharmaceutical
Codex c) Indian Pharmacopoeia d) United State
Pharmacopoeia e) National Formulary f) The State
Pharmacopoeia of USSR g) Pharmacopoeia of other
countries
• Non-official compendia: The books other than official drug
compendia which are used as secondary reference sources
for drugs and other related substances are known as non
official drug compendia. These include a) Merck Index b)
Extra Pharmacopoeia (Martindale) c) The United States
Dispensary
16. DRUG DOSAGE FOR cot’d
Tablet: ► Powdered drug(s)
compressed into a disc
Capsule: ► Soluble small hollow
container, usually made of ------- gelatin
/glycerin used to enclose drug in
powder, granule or liquid form.
► May be used to conceal a -----
bitter taste
,
17. Tablets & Capsule:
Enteric coated tablet / Capsules:
► coated with a substance that will not
dissolve until it reaches the small intestine
► for drugs that are irritating to stomach
or to avoid any other adverse effects in
stomach. e.g. Ibuprofen
DRUG DOSAGE FOR cot’d
18. DRUG DOSAGE FORMS
Tablets & Capsule:
Sustained-release tablet / Capsule:
for continuous release of small doses of
the drug over an extended time period to
duration of action
dosing frequency
compliance
DRUG DOSAGE FOR cot’d
19. Powder: very fine particles of drug(s) for
internal or external use
Effervescent powder / tablet:
► Drug mixed with sodium bicarbonate or
citric acid.
► When mixed with liquid, release carbon
dioxide, causing effervescence
(BUBBLING)
DRUG DOSAGE FOR cot’d
21. Aqueous Solutions: e.g. Enemas -----
administered rectally -- for --- local -- or---
systemic effect
Gargles
Mouth washes
Nasal solutions
Otic solutions
DRUG DOSAGE FOR cot’d
22. Aqueous Solutions:
Syrup: aqueous solution saturated with
SUGAR usually contain a flavoring agent
that assists in disguising the taste of the
drug mixed in syrup
DRUG DOSAGE FOR cot’d
23. Alcoholic Solutions:
Spirit or Essence: Volatile drug
dissolved in alcohol.
Elixir: Spirit that has been sweetened
and/or flavored.
Tincture: Solution made by extracting
from the CRUDE (plant or vegetable) source
those constituents of a drug that are soluble in
alcohol.
DRUG DOSAGE FOR cot’d
24. Aqueous Suspension:
Finely divided SOLID PARTICLES
(POWDERS) of a drug suspended in a
FLUID.
They are NOT DISSOLVED in the
fluid.
DRUG DOSAGE FOR cot’d
25. Emulsion:
A preparation of one LIQUID distributed
in small globules throughout the body
of second LIQUID
The dispersed liquid is the discontinuous
phase, & the dispersion medium is the
continuous phase.
DRUG DOSAGE FOR cot’d
26. Emulsion:
Oil-in-water emulsion
Oil --- is the --- dispersed liquid & aqueous
solution -- is the -continuous phase.
Water-in-oil emulsion
Aqueous solution -- is the – dispersed
phase & oil --- is the ---- continuous phase.
DRUG DOSAGE FOR cot’d
27. Ointment
Drug or mixture of drugs added to a semisolid
base, such as petroleum jelly or lanolin.
Some ointments contain a water soluble base.
- For local effects
skin
eye
- For systemic effect
transdermal application (e.g., nitroglycerine)
DRUG DOSAGE FOR cot’d
28. Lotion:
Liquid medicinal suspension applied
externally. Various lotions are designed for
protection, lubrication, cleansing, cooling,
or antipruritic effects.
Cream:
Emulsions that contain an aqueous base
DRUG DOSAGE FOR cot’d
29. Suppository:
► Drug mixed with a fatty base and molded into
shapes suitable for insertion into the
rectum,
vagina, or
urethra.
► A urethral suppository is called a ---- bougie.
► A vaginal suppository is called a ----- pessary.
► for a local or systemic effect.
DRUG DOSAGE FOR cot’d
30. Aerosols:
Aerosols are particles dispersed in a gas, the
particles being small enough to remain in
suspension for a long time instead of
sedimenting rapidly under the influence of
gravity; the particles may be liquid (fog) or
solid (smoke)
DRUG DOSAGE FOR cot’d
31. COMPOSITION OF TABLET
Active ingredient + other substances
Diluent:Diluent:
Binder:Binder:
Lubricant:Lubricant:
Disintegrator:Disintegrator:
Coloring agent:Coloring agent:
Flavoring agent:Flavoring agent: