Medicinal Chemistry General (Last minute grind)

Question 1

What are the 6 ways to administer drugs?

Answer 1

• Ingestion
• Injection with syringe into:skin, fat, muscle, vein
• Inhalation
• Absorption through skin(cream)
• Absorption via rectum(anal/vaginal)
• Applied into ear/eye(drops)

Question 2

Factors doctors must take in administering drugs

Answer 2

dosage, tolerance of patients, Addiction, side effects

Question 3

How does penicillin work? (simple)

Answer 3

Breaks enzyme needed for making cell walls, killing the bacteria

Question 4

Define bioavailability

Answer 4

The fraction of dosage that reaches target site

- 100% in intravenous

Question 5

Why may bioavailability be less than 100%?

Answer 5

• Polarity of drug may be too little/too much
• Breakdown by stomach acid
• reacts with stomach bacteria

Question 6

Why does polarity in a drug matter?

Answer 6

• Polarity of drug may be too little/too much: If too little, can’t dissolve in blood. If too much, can’t cross blood-brain barrier. This affects whether you should eat

Question 7

What is the therapeutic index

Answer 7

The dosage of a drug between the toxic dose for 50 % of population and the effective dose for 50% of population

Doctors may use LD50 in animals to extrapolate for humans

ED50