Psychopharmacology study questions
Lecture 1: Introduction, brush up basics (neuroanatomy, neurotransmitters; ‘Psychopharmacology’
chapters 1-4)
Which two overarching classes of psychoactive substances can be discerned based on their use?
Recreational drugs and medicinal drugs
What are the different names that are given to medications once they become available for
prescription, and what is the difference between these names?
The names are the code name, the generic name and the brand name.
The difference between these names is that the code name is just a label of the drug in a data base
when its newly synthesized, the generic name is the name of the active ingredient of the medicine
and the brand name is the name that the manufacturers gave the medicine.
What is pharmacokinetics and pharmacodynamics? Describe these terms and understand their
difference.
Pharmocokinetics is defined as the movement of drugs through the body. It describes a drug’s
absorption, distribution, metabolism, and excretion.
Pharmocodynamics is defined as the body’s biological response to drugs. It described how biological
processes in the body respond to or are impacted by a drug.
The difference between the two is that pharmocokinetics is what the body does to the drug and
pharmacodynamics is what the drug does to the body.
Considered known (part of the prerequisites; self-study if unfamiliar): types of neurotransmitters,
types of receptors, common principles of neurotransmitter synthesis (incl. precursors), degradation
(incl. reuptake), principles of communication between cells through receptors and how this influences
the chance of the postsynaptic neuron firing an action potential. → Look at chapter 2-4
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?
Psychoactive substances are prescribed for psychiatric disorders/problems.
Describe the most common mechanisms of modulation of neurotransmission along which
psychoactive substances exert their influence on the brain.
A. Effects on transmitter production
- Inhibition of transmitter synthesis
- Blockade of axonal transport
- Interference with the storage of transmitters
B. Effects on transmitter release
- Prevention of synaptic transmission
- Alteration of synaptic transmitter release
- Alteration of transmitter release through modulation of presynaptic activitiy
C. Effects on transmitter clearance
- Inactivation of transmitter reuptake
- Blockade of transmitter degradation
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,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.
Preclinical:
- Animal research always precedes administration of drugs in humans. It tests the efficacy,
administration mode and safety (possible side effects) of a drug.
Clinical:
Phase 1: Is the substance safe? Testing whether human subjects, mainly healthy volunteers,
tolerate the substance
- Phase 2: Does it work? If the substance is safe, sick people take place of the healthy. The aim is
now to test whether the substance really works against the disease. It often starts with a small
number of patients taking the new drug. First this research is mainly open labeled, which means
that everybody in the study knows which people receive the drug.
- Phase 3: Does it work, and is it better than other existing drugs? When the results in phase 2 are
good, larger trials start with a larger number of patients. In this phase, the new drug is first tested
against a placebo and then against existing treatments.
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?
- An important conceptual bottle neck in the development of new medicines is that it has to pass
through the blood-brain barrier to be effective.
- An important practical hindrance is that the body usually breaks down substances in the body, so
to be effective there should be a specific dose.
- An important financial hindrance is that the development of a drug usually costs years of
research, which is a very costly process. Besides that, medicines must have enough market to be
at least somewhat profitable
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.
Because there can be an interaction of the drug with other bodily substances or other drugs that can
cause unwanted and unforeseen side effects.
Another reason that a drug can have unwanted side effects is that it can have a problem with
specificity of the drug targets. Therefore, the drug can influence other parts in the body and
therefore alter processes that it was not aimed to do.
Describe the golden standard in executing (psycho)pharmacological research: placebo –controlled
and double-blind. Why are these aspects of importance?
A placebo group is necessary to conclude whether the effect is actually from the drug that is
administered or that the effect is specific to the drug.
The study needs to be controlled to make sure that there are no other factors that could influence
the result of the study.
The study should be double-blind to make sure that neither the patients nor the researcher is biased
towards the possible results.
Which result will allow the conclusion that a placebo (fake pill) medicine may be useful in treatment?
If the effect of administering the substance is stronger for the group of patients who had been
administered the drug than for the group that had received the placebo.
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, What is an active placebo?
An active placebo is a placebo that produces noticeable side effects that may convince the person
being treated that they are receiving a legitimate treatment. It can be preferable to have an active
placebo that produces comparable side effects as the drug that is studied.
What is meant with ‘Evidence-based medicine’? Why is this important? What do the conflicting
interests of patients, treating physicians, pharmaceutical industry and policy-makers mean for the
credibility of the different sources of information that you can find, for example on the internet?
Evidence-base medicine means that the medicines are experimentally proven to be effective,
preferably with a placebo controlled double-blind study design. This is important to make sure that
you do not prescribe a costly medicine that is actually not that effective. It is necessary that the
research is performed by an independent source and not by the manufacturar of the medicine itself,
because there could be some bias in the study results of the effectiveness. This could be at the cost
of patients.
Lecture 2: Principles of psychopharmacology (dose-response-curve, receptor-interaction,
pharmacokinetics, tolerance etc; Kenemans chapter 5)
Give a definition of psychopharmacology.
Psychopharmacology is the discipline that attempts to study effects of drugs on behaviour, cognition
and emotion.
What is a dose-response-curve (DRC)?
The dose-response-curve is a curve that represents the dose of a substance (x-axis) against the
effects of that dose (y-axis). It gives insight into how much of a substance must be administered to
achieve a certain effect.
Does the DRC for one particular substance always look the same? What does it depend on? How
about differences between individuals?
The DRC for one substance doesn’t always look the same. It depends for example on which response
you look at (which output parameter on the y-axis). DRCs also vary among individuals, because the
dosage that will produce desired as well as undesired effects differ. The relevant section of a DRC is
for example dependent on a person’s history of use.
What type of responses in a DRC and the relationship between them are especially relevant for
medications?
For medication it is especially important that the range between the desired and undesired effects is
large enough. A bigger therapeutic window is desirable, because than you can choose an optimal
dosage without a big risk of getting the undesired effects.
What is efficacy? Potency? Therapeutic window?
Efficacy refers to the maximum effect achievable for a given drug.
Potency refers to the amount required to produce an effect of a given intensity.
Therapeutic window refers to the range between the desired and the undesired effects of a
substance.
Which considerations are relevant for the individual titration of the optimal dose of a substance?
The amount of desired as well as undesired effects.
What is receptor interaction?
Two substances meet one another and therefore interact on the protein complexes in the brain, the
receptors.
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