4BBY1040, L1 INTRODUCTION TO PHARMACOLOGY
Pharmacology: the science of drugs; their mechanisms of action, effects can be measured,
their discovery, design and development, their actions on the organism and the actions of
the organism on them.
Pharmacology effects:
- Toxicology
- Therapeutics
- Pharmacy
A drug can be defined as ‘a chemical substance of known structure, other than a nutrient or
an essential dietary ingredient, which, when administered to a living organism, produces a
biological effect.’
Drugs that are used therapeutically have three names:
- Chemical name- 2methylpropanoic acid
- Common name- ibuprofen
- Proprietary trade name- nurofen
Drugs are grouped according to therapeutic use e.g.
- Analgesics antihypertensives - antibiotics
Sometimes they are grouped together by mechanism of action e.g.
- Beta-blocker - cyclooxygenase inhibitor
So ibuprofen is a cyclooxygenase inhibitor that acts as an analgesic.
Drugs are exogenous molecule that mimic or block actions of endogenous molecules. The
vast majority of drugs bind to molecular target proteins. These target proteins include:
- Receptors for neurotransmitters
- Enzymes
- Ion channels
- Carrier transporter molecules.
How drugs fit:
- The ‘fit’ depends on the size and flexibility of the drug (steric factors)
- How well they bind to target protein depends on the nature of chemical bonds
between drug and the binding site.
- Once it’s in the binding site, most drugs bind reversibility through hydrophobic and
hydrogen bonds plus weak van der waal forces. Some bind irreversibly through
covalent interactions.
- Ultimately, this leads to the formation of a ligand protein complex which alters the
activity of the protein in some way.
Specificity and selectivity:
- A drug to be effective needs to be very selective in its action; an antihypertensive
drug that lowers blood pressure but at the same time causes severe stomach ache is
not going to be useful in treatment with bp.
Pharmacology: the science of drugs; their mechanisms of action, effects can be measured,
their discovery, design and development, their actions on the organism and the actions of
the organism on them.
Pharmacology effects:
- Toxicology
- Therapeutics
- Pharmacy
A drug can be defined as ‘a chemical substance of known structure, other than a nutrient or
an essential dietary ingredient, which, when administered to a living organism, produces a
biological effect.’
Drugs that are used therapeutically have three names:
- Chemical name- 2methylpropanoic acid
- Common name- ibuprofen
- Proprietary trade name- nurofen
Drugs are grouped according to therapeutic use e.g.
- Analgesics antihypertensives - antibiotics
Sometimes they are grouped together by mechanism of action e.g.
- Beta-blocker - cyclooxygenase inhibitor
So ibuprofen is a cyclooxygenase inhibitor that acts as an analgesic.
Drugs are exogenous molecule that mimic or block actions of endogenous molecules. The
vast majority of drugs bind to molecular target proteins. These target proteins include:
- Receptors for neurotransmitters
- Enzymes
- Ion channels
- Carrier transporter molecules.
How drugs fit:
- The ‘fit’ depends on the size and flexibility of the drug (steric factors)
- How well they bind to target protein depends on the nature of chemical bonds
between drug and the binding site.
- Once it’s in the binding site, most drugs bind reversibility through hydrophobic and
hydrogen bonds plus weak van der waal forces. Some bind irreversibly through
covalent interactions.
- Ultimately, this leads to the formation of a ligand protein complex which alters the
activity of the protein in some way.
Specificity and selectivity:
- A drug to be effective needs to be very selective in its action; an antihypertensive
drug that lowers blood pressure but at the same time causes severe stomach ache is
not going to be useful in treatment with bp.
