2. pharmacology - drug study
What is Pharmacology ?
Science that deals with the effects of drugs on living
system.
Sources, biological effects, therapeutic uses,
adverse effects and interactions of drugs
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3. What is drug ?
Substance that modify the physiological systems or
pathological state for the benefit of the recipient.
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5. Pharmacodynamics:
What the drug does to the body
Drug’s mechanism of action
Pharmacological effects of drug
Adverse effects of drugs
Drug interaction
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6. 6
Pharmacotherapeutics:
Application of pharmacological information together
with disease knowledge for prevention and cure
Selection of drug, dose, duration of treatment
Toxicology:
Harmful effects of drug
Detection, prevention, treatment of poisoning
Study of adverse effects
7. Clinical pharmacology:
Scientific study of drugs in man
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P.kinetic/dynamic investigation in healthy and patients
Evaluation of efficacy and safety, adverse effects
Comparative trails, Surveillance
8. SOURCES OF DRUGS
I. Natural sources
II. Semisynthetic sources
III. Synthetic sources
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12. 3.Trade name: (brand, proprietary name)
Given by a pharmaceutical company
Sole property of the pharmaceutical company
A drug may have many proprietary names
Same company – different name in different countries
Prescription, over-the-counter drugs
Ecospirin, Disprin (for aspirin)
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13. 2.Generic name:
Assigned by - United States Adopted Name (USAN) council
British Approved Name (BAN) council
Used uniformly in all countries
After the drugincludedin pharmacopeia - official name
Aspirin, paracetamol
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14. 1. Chemical name:
Is the name of chemical compound present in a drug
Acetyl salicylic acid, Acetaminophen
Not suitable for prescribing
Number is given before name is framed (Eg: INR00439)
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15. Sources of drug information
Pharmacopeia:
Book containing names of officially approved drugs
with their physical and chemical characteristics.
Eg: Indian Pharmacopoeia (IP)
BP, USP
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16. Non-official references:
Physicians’ Drug Reference (PDR)
Dental Drug Reference (Mosby)
Monthly Index of Medical Specialists (MIMS)
Medical journals:
The Malaysian Journal of Medical Sciences
Medical Journal of Malaysia, BMJ
US Food and Drug Administration (FDA): www.fda.gov16
18. Oral route: Advantages:
Safe, convenient for long use
Painless, self administered
Disadvantages:
Slow onset of action (not used in emergency)
Not suitable - in diarrhoea/vomiting/unconscious cases
- unpalatable/irritant drugs, unabsorbed drug
Aspirin, paracetamol, ibuprofen
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19. Sublingual: Advantages:
Quick onset of action, bypass first pass metabolism
Self administered, terminated by spiting out
Disadvantages:
In children
Bad smell & lipid insoluble drugs
Nitroglycerin for angina
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23. Subcutaneous:
Advantages:
Self administration is possible
Depot can be inserted into sc
Disadvantages:
Slow absorption, not useful in emergency
Suitable only for non-irritant drugs
Eg: Insulin, adrenaline
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24. Intramuscular:
Advantages:
Rapid absorption
Depot injections
10 ml can be given at a time
Useful in vomiting, diarrhea, unconscious patients
Bypass first pass metabolism
Disadvantages:
Sterilization required
Painful, no self administration
Injury to nerve, cause abscess
Eg: gentamicin, streptomycin, kanamycin 24
25. Intravenous: Advantages:
Directly reaches blood
Bypass first pass metabolism, 100% bioavailability
Emergency – fast onset of action
Large volume infused – iv fluids
High irritant drugs is given
Useful in vomiting, diarrhea, unconscious patients
Eg: furosemide, diazepam
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27. Topical: (skin and mucous membrane)
Advantages:
More convenient, encouraging to patient
Efficiently delivered to local lesion areas
Disadvantages:
Local irritation, dermatitis
silver sulfadiazine ointment, diclofenac gel
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29. Advantages:
Self administered, better patient compliance
Prolonged duration of action
Less systemic side effect
Disadvantages:
Expensive
Local irritation causes dermatitis, itching
Patch may fall off unnoticed
scopolamine, nitroglycerine, oestrogen
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30. Inhalational:
Volatile liquids and gases are given for systemic effects
Advantages:
Absorption through alveoli, rapid onset of action
Less dose is enough, so less systemic toxicity
Amount of drug can be regulated
Disadvantages:
Irritation causes bronchospasm and high secretion
General anaesthetics – nitrous oxide, ether, halothane
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31. Drug into subarachnoid space - Intrathecal
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Intrathecal – lignocaine, amphotericin
Intra articular – hydrocortisone