Previous Lectures

Question 1

What are the routes of administration?

Answer 1

• intravenous: injecting into bloodstream
• intramuscular: injecting into muscles
• subcutaneous: injecting under skin
• per os (by mouth)
• inhalation
• insufflation: “snorting”

Question 2

What are the features of each route of administration?

Answer 2

intravenous:
- highest concentration in blood
- broken down quickest

intermuscular:
- fast, painful, high concentration in blood
- effects slightly longer than intravenous

subcutaneous: not as potent but longer effects

per os: v. long effects, takes long time, lower potency

inhalation: thru lungs
insufflation: absorbed by mucus membranes

Question 3

What are the pharmacodynamic actions of amphetamine and cocaine?

Answer 3

amphetamine:

1. affects vesicles
   - go into vesicles & displace DA
   - push DA from vesicles into axon terminal
2. reverse DA transporters, more DA released

cocaine:

1. reuptake inhibitor: blocks DA transporter
2. vesicular transporter: pack more DA than usual into vesicles

Question 4

Do psychostimulants only increase dopamine neurotransmission?

Answer 4

• no, affect multiple monoamine systems
• DAT, NET, SERT all v. similar
• DAT: dopamine transporter
• NET: norepinephrine transporter
• SERT: serotonin transporter