Psychopharmacology

Question 1

pharmacodynamics meaning

Answer 1

how the drug affects the body. response of the drug

Question 2

Pharmacokinetics meaning

Answer 2

the movement of drugs throughout the body

Question 3

Pharmacokinetics involves the study of 4 things - what is it

Answer 3

absorption, distribution, metabolism and excretion of drugs

Question 4

Factors Influencing Drug Effects

Answer 4

weight - the heavier the person generally the more drug they will need
age - primarily a factor with infants, children and older adults
gender - physiological differences between men and women can influence a drugs effect
physiological factors - hydration levels, electrolyte imbalance
pathological factors - disease, hepatic/renal/gastrointestinal dysfunction, vascular disorders, low blood pressure
genetic factors - there is a whole branch of pharmacology (Pharmacogenetics (see Bryant & Knights, 2011, p.147-155) dedicated to studying the unique responses to drugs based on genetic make-up
immunological factors - allergies
psychological factors - placebo effect, health beliefs, adherence
environmental factors - temperature, light, noise
drug tolerance - tolerance occurs when the initial dose of a substance loses its effectiveness over time because the body has got used to the drug

Question 5

Categories of antipsychotics?

Answer 5

Typical and Atypical

Question 6

Describe typical antipsychotics

Answer 6

are the older medications used to treat psychotic symptoms. Their main action is blocking dopaminergic receptors, however, growing evidence suggests that typical antipsychotics also affect other neurotransmitter systems. Typical antipsychotics are, therefore, essentially pharmacologically ‘dirty’ drugs and cause a wide variety of undesirable side-effects.

Question 7

What are the Extrapyramidal side-effects (EPS) of Typical antipsychotics?

Answer 7

Parkinsonian symptoms; tremor, rigidity and brady-kinesia
Dystonia; sustained muscular conditions that produce abnormal postures (opisthotonos, torticollis), difficulty in swallowing and oculogyric crisis
Akathisia; a sense of inner restlessness, unrest or dysphonia. Restless movements, such as rocking from foot to foot, walking on the spot, shuffling and swinging one leg on the other while sitting.
Tardive dyskinesia (TD); is a late onset adverse effect, it is typified by involuntary hyperkinetic, choreo-athetoid movements of the orofacial, limb and truncal regions.

Question 8

Atypical antipsychotics are considered

Answer 8

a major advance over typical antipsychotics, primarily because they are relatively free of extrapyramidal symptoms as they are more selective in targeting dopamine receptors and many also target serotonin receptors.

Question 9

Another major advantage of atypical anti-psychotics is that they suppress the negative symptoms. The biggest problem with atypical anti-psychotics is the

Answer 9

increased risk of diabetes and metabolic syndrome.

Question 10

Atypical antipsychotics. Metabolic syndrome includes

Answer 10

Metabolic syndrome includes weight gain, hypertriglyceridemia along with increased insulin, glucose, and low-density lipoprotein cholesterol levels. Metabolic syndrome is a serious health risk especially when people with schizophrenia and BPAD already have a genetic predisposition to developing diabetes

Question 11

Common side-effects of all antipsychotics?

Answer 11

weight gain
drowsiness
constipation
dizziness
hypersalivation

Question 12

Fairly common side-effects of all antipsychotics?

Answer 12

sexual dysfunction

postural hypotension

Question 13

Rare but life threatening:

Agranulocytosis or Neutropenia (associated with Clozapine). What is this

Answer 13

low white blood cell count, therefore body is unable to fight infections. Requires careful monitoring, weekly blood tests for first 18 weeks of treatment, then monthly blood tests to monitor neutropils. Symptoms of concern - fever, rigor, sore throat, any signs of infection and cognitive changes. Person must be advised to contact doctor immediately if they develop any of these symptoms.

Question 14

Neuroleptic Malignant Syndrome (NMS) (associated with all antipsychotics) -

Answer 14

usually occurs within a few weeks of a drug change, thought to be triggered by blockade of doperminergic receptors in the corpus straitum, resulting in spasticity of skeletal muscles (leading to excessive heat generation), and impaired hypothalmic thermoregulation.

Question 15

Treatment to these effects?

Answer 15

stop the medication, treat the fever, hydrate, use benzodiazepines to relax the muscles

Question 16

Commonly used antipsychotic medications. Name common TYPICAL antipsychotics

Answer 16

Chlorpromazine and Haloperidol

Question 17

Commonly used antipsychotic medications. Name common ATYPICAL antipsychotics

Answer 17

Arpiprizole, Quetiapine, Clozapine

Question 18

What information would you include in an education session for someone who is prescribed clozapine?

Answer 18

That they’ll need blood tests weekly for the first 18 weeks and Symptoms of concern - fever, rigor, sore throat, any signs of infection and cognitive changes. Person must be advised to contact doctor immediately if they develop any of these symptoms.

Question 19

ANTIDEPRESSANTS. You need to know about the three main catergories of antidepressants, these are: there are THREE

Answer 19

Selective serotonin reuptake inhibitors (SSRIs) and related drugs, Tricyclic antidepressants (TCAs), Monoamine oxidase inhibitors (MAOIs)

Question 20

Which antidepressant is First line treatment for depression as have less side-effects

Answer 20

Selective serotonin reuptake inhibitors (SSRIs) and related drugs

Question 21

Describe the action and pharmacokinetics of Selective serotonin reuptake inhibitors (SSRIs) and related drugs

Answer 21

Action: SSRIs block the reuptake of serotonin (5HT) leading to increased neurotransmitter levels in the synaptic cleft and increased stimulation of the postsynaptic receptors.

Pharmacokinetics: They are well absorbed from the gastrointestinal (GI) tract, are metabolised in the liver and excreted in urine and feaces. They are able to cross the placenta and enter breast milk.

Question 22

Selective serotonin reuptake inhibitors (SSRIs) and related drugs Side-effects: name common and uncommon

Answer 22

Common: drowsiness, insomnia, sexual dsyfunction, nausea and vomiting

Uncommon: bruising, dizziness, headache

Question 23

SSRI’s Rare (but potentially life-threatening) side effects? Serotonin syndrome

Answer 23

Symptom onset is usually rapid, often occurring within minutes and is potentially life-threatening. It may occur following therapeutic drug use, interactions between drugs, overdose of particular drugs, or the recreational use of certain drugs.

Mild symptoms - increased heart rate, shivering, sweating, dilated pupils, myoclonus (intermittent tremor or twitching), as well as overresponsive reflexes.
Moderate symptoms - hyperactive bowel sounds, high blood pressure, fever, hypervigilance and agitation

Question 24

Examples of SSRIs and related drugs:

Answer 24

Citalopram (Celexa)
Paroxetine (Paxil, Seroxat)
Fluoxetine (Prozac)
Sertraline (Zoloft, Lustral)

Question 25

The second category of antidepressants is?

Answer 25

Tricyclic antidepressants (TCAs)

Question 26

describe the action and pharmacokinetics of Tricyclic antidepressants (TCAs)

Answer 26

Action: TCAs block the reuptake NE and 5HT leading to increased neurotransmitter levels in the synaptic cleft and increased stimulation of the postsynaptic receptors.

Pharmacokinetics: They are well absorbed from the gastrointestinal (GI) tract and reach peak levels in 2-4 hours. They are metabolised in the liver and excreted in urine. Their half-lives range from 8 to 46 hours. They are able to cross the placenta and enter breast milk.

Question 27

Tricyclic antidepressants (TCAs) Side effects and common TCA drugs

Answer 27

Common: dry mouth, blurred vision, constipation, urinary retention, drowsiness, weight gain.
Examples of TCAs:

Amitriptyline (Elavil, Tryptizol, Laroxyl)
Doxepin (Adapin, Sinequan)
Imipramine (Tofranil, Janimine, Praminil)
Nortriptyline (Pamelor, Aventyl

Question 28

Third category of antidepressants?

Answer 28

Monoamine oxidase inhibitors (MAOIs)

Question 29

Monoamine oxidase inhibitors (MAOIs) action and pharmacokinetics

Answer 29

Action: MAOIs inhibit MAO, an enzyme in the nerves that breaks down NE, dopamine and 5HT. This allows these neurotransmitters to accumulate in the synaptic clefts, causing increased stiumlation of the postsynaptic receptors.

Pharmacokinetics: They are well absorbed from the gastrointestinal (GI) tract and reach peak levels in 2-3 hours. They are metabolised in the liver and excreted in urine. They are able to cross the placenta and enter breast milk.

Question 30

What is unique about MAOIs in terms of side effects?

Answer 30

MAOIs have more side-effects than other antidepressant and also require the person to avoid foods that are high in tyramine (hard cheese, meat and fish that are not fresh, salami and dried meat, soy sauce, tofu, tap beer or home-brew, yeast extracts such as marmite & vegemite) as these in combination with MAOIs can cause a hypertensive crisis (headache, stiff neck, nausea, rapid heartbeat).

Question 31

Examples of MAOIs:

Answer 31

Phenelzine (Nardil)

Tranylcypromine (Parnate)

Question 32

Mood stabilisers are

Answer 32

Mood stabilisers are used in the treatment of bipolar affective disorder and schizo-affective disorders. Mood stabilisers are used for the treatment of manic episodes and the prevention of future episodes.

Question 33

What are the 3 types of Mood stabilisers

Answer 33

Lithium, Anticonvulsants and Atypical antipsychotics

Question 34

What is the the drug of choice for treatment of acute mania and ongoing maintenance?

Answer 34

Lithium

Question 35

Lithiums action and pharmacokinetics?

Answer 35

Action: It is not clear exactly how lithium works, but we know that it mimics the effects of sodium, thereby compromising the ability of neurons to release, activate and respond to neurotransmitters

Pharmacokinetics: It is readily absorbed from the gastrointestinal (GI) tract and reach peak levels in 30 minutes to 3 hours. It follows the same distribution path in the body as water (remember - where water goes sodium (or in this case lithium) follows). Lithium is excreted from the kidneys, although 80 % is reabsorbed, if the person has low sodium levels or is dehydrated then the kidneys will absorb more lithium which can lead to toxic levels

Question 36

Lithium Signs of toxicity:

Answer 36

blurred vision, drowsiness, confusion, slurred speech, increased polyuria or polydipsia, dizziness, vomiting, unsteadiness, clumsiness, severe tremour.

Question 37

Patient education for Lithium

Answer 37

ake with food, drink adequate water, will need regular (3 monthly) blood tests to determine lithium levels, if develop any signs of lithium toxicity see Dr immediately.

Question 38

Anticonvulsants action and the 3 commonly prescribed anticonvulsants?

Answer 38

Action: stabilise nerve membranes throughout CNS, thereby reducing excitability and hyperexcitability.

Commonly prescribed anticonvulsants:

Sodium Valproate (Epilim), Carbamazepine (Tegretol), Lamotrigine (Lamictal)

Question 39

Commonly prescribed atypical antipsychotics: 1 of them is used in acute manic phases…

Answer 39

Olanzapine (Zyprexa) (used in acute manic phase) and Risperidone

Question 40

Anxiolytic medications can be divided into

Answer 40

benzodiazepines (these are known as recorded drugs - as CDHB Fluid and Medication Policy) and non-benzodiazepines.

Question 41

What Anxiolytic medication is drug of choice for short term treatment of anxiety?

Answer 41

Benzodiazepines

Question 42

Examples of commonly used benxodiazepines:

These are all used primarily for anxiety (anxiolytics)

Answer 42

Diazepam (Valium)
Clonazepam (Paxam)
Lorazepam (Ativan)
Alprazalam (Xanax)
Oxazepam (Serepax)

Question 43

People can become physically dependent on benzodiazepines therefore

Answer 43

People can become physically dependent on benzodiazepines therefore these are usually prescribed for short-term use only.

Question 44

Non-benzodiazepines example

Answer 44

Propanalol