NATURE AND SOURCES OF DRUGS

Dr. RAGHU PRASADA M SMBBS,MDASSISTANT PROFESSOR DEPT. OF PHARMACOLOGYSSIMS & RC.

Natural Plants-

AnimalMicro organismsMineral

SYNTHETICThe quality control is better, the process is easier cheaper. The chemical structure of prototype drug can be modifiedEX-aspirin, paracetamol, Phenytoin, Amphetamine

SOURCES OF DRUGS

PLANT SOURCE

SourcePlant DrugUse

Leaf Digitalis Digoxin CHF

Bark Cinchona Quinine Malaria

Fruit Opium Morphine Analgesic

Seed Eserin Anticho Myasthenia.Gravislinestrase

PLANT SOURCEExample Trade Name ClassificationChinchona Bark Quinidine Antiarrhythmic,

Malaria

Purple Foxglove Digitalis Cardiotonic

Poppy Plant Paregoric, Antidiarrheal,(Opium) Morphine, Analgesic,

Codeine Antitussive

Important Pharmacological active principles in plants are:

1)Alkaloids2)Glycosides3)Oils4)Resins5)Gums6)Tannins

PLANT SOURCE

Nitrogenous hetrocyclic bases.Insoluble in water.Form salts with acids, which are soluble in water.

Ex: Drug Plant Atropine Atropa belladonaQuinine Cinchona bark

ALKALOIDS

Drug Plant

Morphine Papavaram somniferum(Poppy)Reserpine Rauwolfia serpentinaNicotine Tobaco leaves

Alkaloids names usually end with “ine”.

ALKALOIDS

These are combinations of sugar with other organic structures.

O Glycoside

O Glucoside

O aminoglycoside

Sugar portion governors the pharmacokinetic characteristic of glycoside.

Sugar Non sugar .

Glycosides

Glucose Non sugar

Aminosugar Non sugar

On hydrolysis with mineral acids all glycoside split up into sugar and non sugar residues.

Ex: Cardiac glycosides Digitoxin, Digoxin are obtained from Fox glove leaves (Digitalis purpurea).

Glycosides

Generally 3 types of oils are used for medical purposes.

i) Essential oils (Volatile oils)ii) Fixed oils.iii) Mineral oils

Oils

Obtained from leaves or flower petals by steam distillation.Terpene derivative so these have aroma Steam volatile No food value (caloric)Do not from soaps with alkaloidsThey do not rancid (Foul smell) on prolong stay

Essential oils (volatile oils)

Uses:- Carminatives:- For expulsion of gas from stomach. Ex:-Ginger, eucalyptus oil. (act as irritant to gastric mucosa)

Antiseptic:- Mouth washes.

Flavouring agents:- Peppermint oil

Pain relieving agents:- Clove oil for toothacheActs as counter irritant

Essential oils (volatile oils)

Fixed oilsGround nut oil, coconut oil, olive oil, caster oil (purgative)Obtained by solvent extraction of crushed seeds.Saturated from Animal Unsaturated from Plant Non volatile, have caloric valueForm soaps with alkaloidsBecome rancid on prolong stay

Mineral oils

Mostly petroleum productsObtained by dry distillation of wood.Have no calorific value and do not become rancid on prolonged useEx:- Liquid paraffin (hydrocarbon derived from petroleum)Uses:-Lubricant laxative for promote defecation.

These are polymers of volatile oils and insoluble in water.Ex: Benzoin

Use:Used as inhalational in common coldTreatment in cough

Resins

Secretary products of plants These are dispersible in water and form adhesive mucilaginous colloids

Ex:- Gum acacia

Uses:-Emulsifying or suspending agents.

Gums

Non nitrogenous phenolic derivatives from plant.Soluble in water.

Ex:- Astringents (precipitate surface proteins)

Tanins

Obtained from animal Drug AnimalHeparin LeechInsulin Pork pancreasThyroxin Thyroid Vit. B12 Liver extractCod liver oilAnti toxic sera

Animal source

AnimalsExample drugPancreas of Cow, Insulin; regular,

AntidiabeticPancreas of pork Hormone

Stomach of Cow, Pepsin Digestive Hormone

Thyroid Gland Thyroid, USPHormoneOf Animals

Animal source

Bacterial, Fungi, Moulds imp source of many life saving drugs.These obtained from MO and used to kill Microorganisms.

Drug MicroorganismPenicillin Penicilium notatumChloramphenicol Streptomyces venezuelaceGriseofluvin Pencillin grisofullivumStreptomycin Streptomyces griseusNeomycin Streptomyces fradiae

Micro organisms

Use in pharmacotherapy

Mineral UseFerrous sulfate(FeSo4) AnaemiaMagnesium sulfate(MgSo4) Purgative Sodium bicarbonate (NaHco3) AntacidAluminum Hydroxide Antacid

Mineral source

Example Trade Name ClassificationMagnesium Milk of Magnesia Antacid,

Laxative

Zinc Zinc Oxide Oint. Sunscreen, Skin

Protectant

Gold Auranofin Anti-inflammatory;

Used in Rheumatoid Arthritis

Mineral source

Presently majority of drugs are obtained syntheticallySome of drugs which are earlier obtained from plant today synthesized in lab.

Advantage Quality can be controlledProcess is easier and cheaperMore potent and saferLarge scale production

Synthetic

Example Trade Name ClassificationMeperidine Demerol Analgesic

Diphenoxylate Lomotil Antidiarrheal

Co-Trimoxazole Septra Anti-Infective Sulfonamide; Used in the treatment of

UTI’s

Synthetic

These are mainly obtained by changing the chemical structure of natural obtaining drugs. Ex: Atropine bromide

Penicillin substrates.( by changing –R side chain)

Semi synthetic

HCG(Human Chorionic Gonadotropin) Pregnant womenMenotrophin Post Menopausal women urineRegular insulin Human Urokinase Human kidney cellsGHRH(Growth Hormone Releasing Hormone) Human

Human source

Relatively new methodology involves the blending of discoveries from molecular biology, rDNA technology, DNA alteration, Gene splicing, immuno pharmacology.

Ex:-Hepatitis-BInsulin (Human insulin of rDNA techniques)

Genetic engineering

Download slides from slideshare-raghuprasadaauthorstream-raghuprasadaYOUTUBE-raghu prasada