11.1 (clinical) - Drugs in Psych

Question 1

What are the 3 main targets of anti-psychotic drugs?

Answer 1

Dopamine (D2)
Serotonin (5-HTA)
Muscarinic ACh

Question 2

What are the conventional 1st generation antipsychotics?

Answer 2

Phenothiazines (chloropromazine and haloperidol)

Question 3

What are the extra-pyramidal effects of antipsychotics?

Answer 3

Acute dystonia

Tardive dyskinesias

Question 4

What are the endocrine effects of antipsychotics?

Answer 4

Blocking the D2 receptor can increase prolactin secretion causing gynaecomastia

Question 5

What are the anti-muscrainic SE of antipsychotics?

Answer 5

Blurred vision, dry mouth, urinary retention

Question 6

What are the cardiac SE of antipsychotics?

Answer 6

Prolonged QT interval, potential drug interactions

Question 7

What are the drug specific SE of chloropromazine and clozapine?

Answer 7

chloropromazine: cholestatic jaundice
Clozapine: bone marrow suppression

Question 8

What are the 3 broad classes of anti-depressants?

Answer 8

Monoamine re-uptake inhibitors
Monoamine receptor antagonists
Monoamine oxidase inhibitors

Question 9

What are the monoamine re uptake inhibitors?

Answer 9

SSRI: fluoxetine and citalopam
TCA: amitriptyline
NA and 5-HT mixed: venlafaxine
Herbal: St John wort

Question 10

What is the proposed action of anti-depressants

Answer 10

Enhance 5-HT mediated transmission (elevating mood)

NA transmission relieving biological symptoms

Question 11

How do MAO inhibitors work and example

Answer 11

MAO metabolises intracellularly and an inhibitor in the presynaptic terminal will get an increase in presynaptic stores of the NT
Phenelzine (irreversible)
Maclobemide (reversible)

Question 12

How does lithium work and what is it used to treat?

Answer 12

It is a monovalent cation substitute for Na in excitable tissue which can be transported in but not out
Has the ability to effect intracellular metabolic pathways
Not used as a single agent

Used to treat mania - effects secondary to intracellular metabolic effects affecting critical pathways

Question 13

What are the toxicity effects of lithium?

Answer 13

Concentration dependent
Renal: polyuria as inhibits ADH -> longer term renal tubular damage
Goitre: common 40-50%, hypothyroidism

Question 14

What are the drugs used for anxiety?

Answer 14

Anti depressants (SSRI)
Benzodiazepines
Antipsychotic drugs

Question 15

How do benzodiazepines work?

Answer 15

Act on the GABAa receptors which mediate inhibitory synaptic transmission in the CNS by opening chloride channels
Binds to the regulatory site on the receptor and allosterically increases affinity of the receptor for GABA

Question 16

What are the effects and SE of benzodiazepines and what is the competitive antagonist?

Answer 16

decreased anxiety and aggression 
Induced sleep and sedation 
Dcrease muscle tone and co-ordination 
Anticonvulsant 
Anterograde amnesia 

SE: Acute overdose, tolerance and depedance

Antagonist: Flumazenil