GENERAL PHARMACOLOGY - INTRODUCTION DENTAL.ppt

DENTAL

1. PHARMACOLOGY

2. PHARMACOLOGY BOOKS
1.ESSENTIALS OF PHARMACOLOGY FOR
DENTISTRY -K.D.TRIPATHY(3
RD
EDITION)
2.PHARMACOLOGY AND
PHARMACOTHERAPEUTICS –R.S.SATOSKAR
(24
TH
EDITION)
3.BASIC AND CLINICAL PHARMACOLOGY –
BERTRAM G. KATZUNG -(13
TH
EDITION)

4. PHARMACOLOGY
GENERAL PHARMACOLOGY
SYSTEMIC PHARMACOLOGY
ANTI MICROBIALS AND DRUGS
IMPORTANT IN DENTAL
THERAPEUTICS

5. GENERAL PHARMACOLOGY

6. How to do well in pharmacology
Understand:
how general pharmacology principles apply to the drugs
the mechanisms involved in the therapuetic effects of
drugs
Memorize: (sorry!)
drug names
pertinent facts about drugs
Combine both types of knowledge to make rational choices
for treating patient
Don’t get behind!

7. The pharmacology learning tree
Prototype Name
Drug Class
Mechanism of action
Therapeutic
use
Adverse/toxic
effects
Unusual kinetic
properties
Miscellaneous information: contraindications, route
of administration, etc.
More important
Less important

8. What is Pharmacology ?
The term pharmacology---Greek words
Pharmakon -drug or medicine
logos-the truth about or science
The science of drugs

9. What is Pharmacology ?
DEFINITION
Pharmacologyis the study of how drugs exert their
effects on living systems.
What is a Drug?
A DRY HERB
Chemical agent used in the diagnosis, treatment or
prevention of disease

10. Drugs (WHO)
Drugs can be defined as any substance or product
that is used or intended to be used to modify or
explore physiological system or pathological states
for the benefit of the recipient

11. Is the study of
Pharmacology
How drugs interact
with the body
Specific drugs and
specific applications
Basic principles and
mechanisms of
action
Interactions on
cellular and organ
system levels
And includes
the study of
Pharmacology concept map

12. Pharmacology
Pharmacokinetics Pharmacodynamics
What body does to drug What drug does to body

13. Pharmacodynamics includes physiological and biochemical
effects of drugs and their mechanism of action at organ system /
subcellular/ macromolecular levels.
Pharmacokinetics describes the movement of the drug in and
alteration of the drug by the body ; includes absorption,
distribution, binding/ localization / storage, biotransformation and
excretion of the drug.

14. •examines the effects of genetic factors to
variations in the drug response
pharmacogenetics
•The application of pharmacological information
together with knowledge of the disease for
prevention, mitigation or cure.
Pharmacotherapeutics
•studies the undesirable effects of chemicals on
living systems
•(includes poisons, antidotes and unwanted side
effects of drugs)
Toxicology
•The art of preparing, compounding and
dispensing chemicals formedicinal use
pharmacy

15. Primitive
Herbal Remedies
Arrow Poisons
Mood altering foods
Opium ,Cocoa
Ancient
Preservation substances (Egyptian
Mummification)
100 A.D. = 600 substances listed in the
Roman “MateriaMedica”
Medieval
Plants and herbs are classified
Relationship of dose to toxicity is recognized
Use of poisons for homicide prevalent
17
th
and 18
th
Century
Increased knowledge of drugs
Widely accepted by physicians and lay persons
19
th
Century
The beginning of the modern science of pharmacology
History of Pharmacology

16. Drug Nomenclature
Drugs are identified by one of 3 names
Chemical –chemical structure of the drug
Nonproprietary–Competent scientific body/ authority .
(USAN, BAN)
Generic, Approved & official Names
Proprietary –Trade/brand name assigned by the
manufacturer

17. ChemicalName Non-proprietary
name
Property name
Acetyl salicylic acidAspirin Ecospirin,
Bayers,
Aspirin,
Dispirin.
P-Acetaminophenol Paracetamaol Crocin,Calpol
AminobenzylpenicillinAmpicillin Biocillin,
Sythocillin,
Roscillinm,
Albercillin
1-(Isopropylamino) -3-
(1-naphthyloxy)
propan-2-ol
Propranolol Inderal,Ciplar,
Betabloc.

18. PHARMACOPOEIA
Anofficialcodecontainingaselectedlistoftheestablished
drugs&medicinalpreparationswithdescriptionsoftheirphysical
propertiesandtestsfortheiridentity,purityandpotency.
Examples
The Indian pharmacopoeia (IP),
The British pharmacopoeia (BP),
The United States pharmacopoeia. (USP) and
The European pharmacopoeia.
Sources of Drug Information

19. Sources of Drugs
Plants
Example Trade Name Classification
Chinchona Bark Quinidine Antiarrhythmic
Purple FoxgloveDigitalis Cardiotonic
Poppy Plant Paregoric, Antidiarrheal,
(Opium) Morphine, Analgesic,
Codeine Analgesic,
Antitussive

20. Sources of Drugs
Minerals
Example Trade Name Classification
Magnesium Milk of MagnesiaAntacid, Laxative
Zinc Zinc Oxide Oint.Sunscreen, Skin
Protectant
Gold Solganal, AuranofinAnti-inflammatory;
Used in Rx of
Rheumatoid arthritis

21. Animals
Example Trade Name Classification
Pancreas of Cow,Insulin; regular,Antidiabetic
Hog NPH, PZI Hormone
Stomach of Cow,Pepsin Digestive
Hog Hormone
Thyroid GlandThyroid, USP Hormone
Of Animals
Sources of Drugs

22. Sources of Drugs
Synthetic
Example Trade Name Classification
Meperidine Demerol Analgesic
Diphenoxylate Lomotil Antidiarrheal
Co-trimoxazole Bactrim, Septran Anti-Infective
Sulfonamide;
Used in the treatment of UTI

23. Essential Drugs concept
Those that satisfy the priority health care needs of the population
Ist model list of Essential Drugs -1977
India –“National List of Essential Medicines” -354 drugs

24. Essential Drugs concept
I
•Adequate data on its efficacy and safety
should be available from clinical studies.
II
•Assured quality, including bioavailability, and
stability on storage
III
•Choice should depend upon pattern of prevalent disease;
availability of facilities and trained personnel; financial
resources; genetic, demographic and environmental factors.

25. IV
•Two or more similar medicines, choice should
be based on of their relative efficacy, safety,
quality price and availability. Cost-benefit
ratio.
V
•Choice may also influenced by comparative
pharmacokinetic properties and local facilities
for manufacture and storage.
VI
•Should be single compounds. Fixed ratio
combination -effect, safety
Essential Drugs concept

26. VII
•Selection should be a continuous process based on
the changing priorities for public health action,
epidemiological conditions, availability of better
medicines / formulations and progress in
pharmacological knowledge.
VIII
•Recently, it has been emphasized to select
essential medicines based on rationally
developed treatment guidelines.
Essential Drugs concept

27. WHO Essential medicine list –1977
Revised & latest –2017 with 433 drugs&
25 FDC
National list of Essential drugs –1996
Revised in 2015 & latest –376 drugs &
20 FDC
Essential Drugs concept

28. ROUTES OF DRUG ADMINISTRATION

29. Definition
Aroute of administrationis the path by which a drug,
fluid, poison or other substance is brought into contact
with the body

30. Factors governing choice of route
1.Physicaland chemical properties of the drug
2.Site of desired action
3.Rate and extent of absorption of the drugs form different routes.
4.Effect of digestive juices and first pass metabolism on the drug.
5.Rapidly with which the response is desired
6.Accuracy of dosage required
7.Condition of the patient

31. Routes of drug Administration
1. Enteral
2. Parentral
3. Topical

32. III. Topical Routes
a. Transdermal
b. Conjunctival
c. Vaginal and
urethral
d. Inunction
(rubbing)
II. Parenteral
Routes
a. Intravenous
b. Intramuscular
c. Subcutaneous
d. Intra -arterial
f. Intramedullary
g. Intra -articular
h. Intraperitoneal
i. Inhaltion
I. Enteral
Routes
a. Oral
b. Sublingual
c. Rectal

33. EnteralRoutes
Enteral-Drug placed directly in the GI tract
sublingual-placed under the tongue
oral -swallowing
rectum -Absorption through the rectum

34. Oral
Advantages
Convenient-can be self-administered, pain free, easy to take,
No assistance is needed, safe, Noninvasive.
solid & Liquid dosage forms can be given
Absorption-takes place along the whole length of the GI tract.
Cheap-compared to most other parenteral routes

35. Disadvantages
Action is slow & not suitable for emergencies
Unpleasant taste of some drugs
unconscious / uncooperative patient -NO
Destruction of drugs by gastric acid and digestive juices
Sometimes inefficient -only part of the drug may be absorbed
First-pass effect -drugs absorbed orally are initially transported to
the liver via the portal vein
Irritation to gastric mucosa -nausea and vomiting

36. First-pass Effect
Drugwhichisabsorbedfromthegutanddeliveredto
theliverviatheportalcirculation.
Thegreaterthefirst-passeffect,thelesstheagentwill
reachthesystemiccirculationwhentheagentis
administeredorally

38. Sublingual/Buccal
Somedrugsareplacedunderthetongueorcrushedinthe
mouth&spreadoverthebuccalmucosa
e.gGTN,Buprenorphine,Desaminooxytocin
Advantages
rapid absorption to systemic circulation
drug stability
avoid first-pass effect
Spit out the drug
Disadvantages
inconvenient
small doses
Irritant or unpleasant taste --some drugs

39. Rectal Administration
Through rectum –suppositories, retention enema
Merits:
i. useful in patients with nausea and vomiting, unconsciousness
ii. First –pass degradation is largely bypassed (major
portion of the drug is absorbed form external
hemorrhoidal veins )
iii. Useful for gastric irritant drugs also.

40. Demerits:
(i)Chancesofrectalinflammation
(ii)Absorptionisunreliableand
(iii)Inconvenientandembarrassingtothepatient.
e.gDulcolaxandglycerinesuppositories
Diazepam,paraldehyde,ergotamine.

41. ParenteralRoutes
•Intravascular(IV, IA)-placing a drug directly into the
blood stream
•Intramuscular(IM) -drug injected into skeletal muscle
•Subcutaneous-Absorption of drugs from the
subcutaneous tissues
•Inhalation-Absorption through the lungs

42. Intravascular
1. Precise, accurate and almost immediate onset of action
2. Large quantities can be given, fairly pain free
3. For unconscious, uncooperative & Vomiting patient.
4. Food, Digestive juices -DO NOT interact.
Absorption phase is bypassed
(100% bioavailability)
Greater risk of adverse effects
a)Aseptic condition, costly, Invasive, Assistance
b)cannot inject oily drugs
c)risk of embolism or necrosis

43. Intramuscular Injection
Site
Deltoidmuscleorglutealmassofleftorrightbuttock.
Vastusmuscle-lateralsurfaceofthethigh,
Triceps,Recusfemoris.,
---analternativeareas.

44. Meritis
(i)Absorptionismorepredictable
lessvariableandcomparedtooralroute.
rapid
(ii)Depotinjectionscanalsobegiven
(oilysolutions,aqueoussuspensions)
Demeritis
(i)Perfectasepticconditionsareneeded,
(ii)ChancesofabscessatthesiteofInjection,
(iii)Chancesofnervedamage--paresis
(iv)Largevolumescannotbeadministered.
e.g:Varousantibiotics,antiementicsand
depotinjectionoftestosterone.

45. Subcutaneous
Injected into Loose subcutaneous tissue
1.Slow and constant absorption.
2. Limited Absorption ---by blood flow circulatory failure.
3. Concurrent administration of vasoconstrictor will slow absorption
e.g –local anesthetics, vaccines, insulin.
Heparin

46. Subcutaneous
Pellet implantation
Trochar & cannula
Release over weeks & months
e.g. DOCA , Testosterone
Dermojet
Microfine orifice is used
High velocity jet drug solution
Painless & mass inoculations
Sialistic and biodegradable implants
Drug packed in tubes& capsules
implanted under the skin
e.g Contraceptives

47. IntraperitonealAdministration
Site:Into the peritoneal space.
Merits: Rapid absorption ---larger surface area.
Demerits:Painful
risky Adhesions and
Infections in peritoneal cavity
(peritonitis)
Asepticconditionsareneeded
e.g.,Antirabiesinjection
Peritonealdialysis-poisoningandrenalfailure.

48. INTRATHECAL (INTRASPINAL) ADMINISTRATION
Into the subarachnoid space
Merits -Acts directly on meningesand the CNS.
Demerits
Strict aseptic conditions,
Great experience is needed
painful and risky procedure
e.g
iRadiopaquecontrast media for myelography
( to visulailsespinal cord )
ii. Xylocaineinjection ---spinal anaesthesia.

49. IntramedullaryAdministration
Site: Injection into the tibialor sternalbone marrow.
Merits:
Onset of action very fast (as the vascular spaces of bone
marrow communicate directly with the large veins)
Demerits:
Risky & painful,
skill and strict aseptic precautions are needed
e.g.
Bone marrow transplantation.
Sometimes IV fluids transfused by this route in children,
if veins are not available.

50. Intra-arterial Administration
Site: Into the lumen of the desired artery.
Merits
Greater concentration of the drug delivered ---desired site of action
Demerits
Greatexpertiseandasepticconditionsarerequired.
e.g.Radiopaquecontrastmediaforcoronaryangiographyand
cerebralangiography.
Anticancerdrugs(nitrogenmustard)
---malignancyinvolvinglimbs.

51. Intra-articularAdministration
intothejointspace
Merits:higherconcentrationofdruginalocalizedarea.
Demeritis
Strictasepticconditionsareneeded
Repeatedadministration---damagethejoint.
Painfulprocedure.
e.g.Hydrocortisoneorgoldchlorideinjection-rheumatoidarthritis.

52. Inhalation
Site:Inspiration through nose or mouth.
Merits:
(i) Faster absorption and quick onset of action due to larger
surface area of alveoli and
(ii) Self administration is also possible.
Demerits:
Bronchial irritation --increased bronchial and salivary secretions.

53. e.g.
Oxygenandgeneralanaestheticsinhalation
MeteredaerosolpreparationsofSalbutamol--bronchialasthma.
By Mouthpiece By Mask

54. Topical
Skin
a. Dermal –ointment, cream, lotion, paste, powder, spray etc.,
(local action)
b. Transdermal-absorption of drug through skin (systemic
action)
i. stable blood levels
ii. no first pass metabolism

55. Mucosal membranes
Mouth & pharynx -paints, lozenges, mouth washes, gargles
Eyes, ear & Nose -Eye drops, oinment, irrigation, nasal spray.
GIT-Magnesium hydroxide, sucralfate, Neomycin.
Urethra-Jellys-lidocaine
Irrigating solutions
Vagina -Pessaries, tablets, Inserts, Cream, powders,Douches.
Anal canal -oinment, Suppositories.

56. Why Novel Drug
Delivery system?
To optimize drug’s therapeutic effect,
convenience and dose
To enhance a product’s life-cycle
To improve `patient compliance
To target drug delivery
To control overall healthcare costs
To facilitate biological drug delivery

58. Questions???