Hoorcollege 1 - introduction
1. Which two overarching classes of psychoactive substances
can be discerned based on their use?
- Recreational drugs: substances have a rewarding effect, which
increases the likelihood that it will be used again.
- Medicinal drugs: used to reduce, change or control problematic
behaviour.
2. What are the different names that are given to medications
once they become available for prescription, and what is the
difference between these names?
- Chemical name
- Generic name
- Brand name (patent holder)
3. What is pharmacokinetics and pharmacodynamics? Describe
these terms and understand their difference.
- Pharmacokinetics: how does a substance move through the body?
How does the body treat the substance (e.g. absorbs or secretes
it)
- Pharmacodynamics: how does a drug have effect on the body?
Here we look at the receptors and the interactions with
neurotransmitters.
4. Medications have a certain indication, meaning the illness,
symptoms or disorder for which they are prescribed. In
general, within which area do the indications for
psychoactive substances fall?
- They alter mood and perception.
5. Describe the most common mechanisms of modulation of
neurotransmission along which psychoactive substances
exert their influence on the brain.
- Psychoactive drugs alter synaptic transmission by modulating
neurotransmitter amount and availability or by affecting receptor
activity.
6. Many of the currently used psychoactive substances have
been discovered by serendipity, but once every so often new
medications are developed on purpose through hypothesis-
driven research lines. Describe in broad terms the
(pre)clinical development phases which a new medicine has
to pass before it can be made available to patients.
- It has to be admitted by CBG/EMA/FDA
o Preclinical phases (animal research precedes administration in
humans)
Efficacy (animal models not always predictive for effects
in human)
Administration (Does the substance survive the gastro-
intestinal system? And the blood-barrier)
Safety (are there no serious side effects, even when
administered systematically?)
- Clinical trials (in humans)
1
, o Phase 1: non-toxic, tolerable
o Phase 2: limited efficacy studies
o Phase 3: Large, multi-center studies
o Phase 4: Monitoring after introduction
7. In the development of new medicines, there are many bottle
necks. What are the most important conceptual bottle necks
(think for example of brain mechanisms that cause the
disorder)? And what are the most important practical
hindrances (for example, think of pharmacokinetic
properties)? And what are financial hindrances?
- Blood-brain barrier
- Getting financial support to do research
8. There are various reasons why most psychoactive
substances not only exert their main (intended) effect, but
also unwanted side-effects. Describe the two most important
reasons.
- Receptors are located in different parts of the brain, so it can affect
different mechanisms, leading to side effect.
- The body reacts to the drugs
9. Describe the golden standard in executing
(psycho)pharmacological research: placebo –controlled and
double-blind. Why are these aspects of importance?
- Avoids reporting bias
- Produces objective results, since expectations of researcher or the
participant do not affect the outcome.
10. Which result will allow the conclusion that a placebo
(fake pill) medicine may be useful in treatment?
- The drug may have had the expected effect, but that effect was just
as strong in the placebo group.
11. What is an active placebo?
- A placebo that produces noticeable side effects that may convince
the person being treated that they are receiving legitimate
treatment.
12. What is meant with ‘Evidence-based medicine’? Why is
this important?
- Medicine that uses scientific methods to organize and apply current
data to improve healthcare.
Hoorcollege 2 – principles of psychopharmacology
13. Give a definition of psychopharmacology.
- Psychopharmacology concerns the effect of psychoactive substances
on behaviour and brain.
14. (See also Kenemans, paragraph 1.2) What is a dose-
response-curve (DRC)?
- A DCR has on the x-axis an increasing dose of a substance and on
they y-axis a subjective report, objective observation of behavior or
brain process. So the effect depends on the dose and the response
as function of dose.
- What can you learn from a DCR?
2
, o The potency
o The efficacy
o The therapeutic window
15. See Kenemans Fig. 5.2: Does the DRC for one particular
substance always look the same? What does it depend on?
How about differences between individuals?
- No! The DRC is different for different outcomes and substances.
There are individual differences.
16. What type of responses in a DRC and the relationship
between them are especially relevant for medications?
- The lowest dosage with an effect, the lowest dosage with the
maximum therapeutic effects and the highest dosage with minimum
side-effects are important types of responses.
17. Wat is efficacy? Potency? Therapeutic window?
- Efficacy: maximum attainable effect
- Potency: quantity of drug dose necessary to produce a given effect.
- Therapeutic window: the relation between the dose people show the
intended effect and the dose in which people start to show side
effect.
18. Which considerations are relevant for the individual
titration of the optimal dose of a substance?
- For most psychoactive drugs the desired effect is only achieved after
chronic administration, usually for a period of 2-6 weeks.
- The initial dose must be administered for weeks before a balance
can be determined between the desired and undesired effect.
19. What is receptor interaction?
- Substances meet one another and interact on the protein complexes
in the brain.
20. What is the relationship between receptor interaction
and statistical interaction?
- One substances effect on behavior changes under the influence of a
second substance
- The effect of a substance and the effect of a change in task.
21. What is the importance of a statistical interaction
between a pharmacological variable and a psychological
variable?
- Then it is clinical significant.
22. With receptor interaction, what is affinity, en what is
efficacy?
- Affinity: how well a substance binds to a receptor
- Efficacy: the degree to which the bond between the neurotransmitter
and the receptor result in a synaptic effect.
23. (See also Kenemans paragraph 4.4) In what respect do
full and partial agonists differ, in affinity or efficacy?
- Full agonists have high affinity and high receptor efficacy.
- Partial agonists have a high affinity, but their receptor efficacy lies
somewhere between that of a full agonist and an antagonist.
24. (See also Kenemans paragraph 4.4) What is high with a
pure antagonist, affinity, efficacy or both?
3
