L1: INTRO TO OCULAR PHARM (MCQ)

Question 1

What is pharmacology & its relations to the eye

Answer 1

unified study of the properties of chemical
& living organisms and all aspects of their interactions

take medication or apply meds for eye, will reach systemic circulartion and to be eliminated eventually e.g urination, saliva, perspiration etc

Question 2

how do we Identify drugs? (brand name, generic name, chemical name)

Answer 2

brand name: given by drug company
generic name: common name
chemical name

e.g:
Brand Name: Panadol
Generic Name: Paracetamol
Chemical Name: N-acetyl-p-aminophenol, 4-hydroxyacetanilide, P-hydroxyacetanilide, P-acetaminophenol, P-acetylaminophenol

Question 3

what is Pharmacodynamics

Answer 3

Pharmacodynamics: biological & therapeutic effect of the drug, what a drug does to the body

where and how drugs act on an organism to produce the effect

Question 4

What is Pharmacokinetics

Answer 4

what the body does to the drugs, what happens to the drug with the passage of time
e.g absorption, distribution, metabolism and elimination

Question 5

what is a drug?

Answer 5

A bio-active molecule that is not normally a part of the
body.
A chemical that alters the function of a living system.

Question 6

WHAT HAPPENS WHEN THE DRUG ENTERS THE BODY?

Answer 6

drug binding occurs for the reaction to take place
D[Drug/ligand] + R [Receptor] = DR [Pharmacological Effect]

Question 7

what is the law of mass action?

Answer 7

Rate of reaction is proportional to the concentration of the reactants
(Applies to both agonist & antagonist)

Question 8

what is the definition of Agonist

Answer 8

agonist: a drug that has affinity for receptor and stimulates physiological activity (activates the receptor)

Question 9

2 IMPORTANT PROPERTIES ASSOCIATED WITH AN
AGONIST?

Answer 9

1. affinity: ability or tendency to find to receptor
2. efficacy: ability to activate the receptor and produce a response

these 2 factors contribute to drug potency (how strong it is)

Question 10

what are the 2 types of agonists?

Answer 10

1. partial agonist: : may occupy all the receptors but produces lower response than a full agonist
2. full agonist: may produce the maximum response by binding only to a fraction of the receptors.

Question 11

what makes a drug potent?

Answer 11

lower dose and producing high effect

Question 12

what is ED (effective dose) 50?

Answer 12

Dose level producing a response that is 50% of the maximum

Question 13

what is the definition of antagonist

Answer 13

antagonist: drugs that block action of other substances without producing any physiological effect

Question 14

what are the 3 types of antagonists?

Answer 14

1. Competitive: competes for binding site with agonist, Can be overcome with increasing agonist
2. Non-competitive: Reduces agonist effect by acting on some
   other site, cannot be overcome with increasing agonists
3. Irreversible: Binds irreversibly to receptors, Effects cannot be overcome, no change in antagonist occupancy no matter how
   high the agonist concentration is.

Question 15

what are the 2 types of drug administration?

Answer 15

1. local/topical: Drugs exerts effect near or at the site of administration. e.g eyedrops
2. systemic: Drug enters bloodstream e.g oral (pills), parenteral (injection/IV)

Question 16

give e.g of oral systemic administration. where is it absorbed?

Answer 16

Most common
* Exists in capsules, tablets, fluids
* Absorption occurs at small intestine

Question 17

give 3 e.g of parenteral systemic administration. where is it absorbed?

Answer 17

Drugs enter systemic circulation without
deactivation by liver.

1.subcutanous: Insulin
2. intramuscular: Vaccination
3. Intravenous: enters systemic circulation immediately,
fastest route of administration

Question 18

what is bioavailability?

Answer 18

Describes the amount of drug present at the
desired receptor site.

Question 19

how do drugs get absorbed?

Answer 19

After administrating a drug, it gets absorbed.
Eg. From intestines to bloodstream.

• Drugs get absorbed through passive movement across the cell membrane driven by a concentration gradient.

Question 20

how do drugs get distributed? 3 steps? DMU

Answer 20

Drugs distribute in the body driven by blood circulation

Steps in distribution:
* Dilution in blood
* Movement into extracellular fluid
* Uptake into cells

Question 21

how do drugs get eliminated?

Answer 21

Removal of drug from the body involves 2 processes:
* Metabolism: Chemical alteration of a drug into a different form.
Occurs mainly in the liver (biotransformation.)

-excretion: transfer of a drug from the inside to the outside of the body. Occurs mainly in the urine via kidney
other e.g: feces, lungs, breast milk, perspiration, saliva, tears

Question 22

DRUG ROUTE IN THE HUMAN BODY?

Answer 22

1. Administration
2. Absorption
3. Distribution
4. Elimination