Psych medications

Question 1

What is the first line treatment for patients with schizophrenia (2005 NICE guidelines)?

Answer 1

Atypical antipsychotics

• Because they have significant reduction in extra pyramidal side effects

Question 2

What are examples of atypical antipsychotics?

Answer 2

[-pines] clozapine - quetiapine - olanzapine

But also:
risperidone
amisulpride
aripiprazole

Question 3

What are the adverse effects of atypical antipsychotics generally?

Answer 3

Weight gain & hyperprolactinaemia

Question 4

If a patient has effects of hyperprolactinemia e.g. breast tenderness, enlargement and lactation, what atypical antipsychotic is best?

Answer 4

aripiprazole - due to a generally good side effect profile, particularly for prolactin elevation

Question 5

What are the higher risks involved with olanzapine?

Answer 5

higher risk of dyslipidemia and obesity

Question 6

What are the risks of clozapine?

Answer 6

effects on: 2 blood, bowels, brain, heart and 2 mouth
- Agranulocytosis is a significant risk (1%) and TF need FBC monitoring during treatment e.g. clozapine clinics
[- ALSO thats why clozapine should only be used in patients resistant to other antipsychotic medication]
- neutropaenia (3%)

• reduced seizure threshold –> may induce seizures in up to 3% of patients
• Constipation
• Myocarditis (take baseline ECG before star e.g t wave inversion and saddle ST)
• Hypersalivation
• Starting/stopping smoking changes = need clozapine dose adjustment

Question 7

How do tricyclic antidepressants work?

Answer 7

They inhibit the reuptake of NA and 5-HT (5-hydroxytryptamine)

Question 8

What are tricyclic antidepressants used for?

Answer 8

NB: falling out of fashion due to cardiotoxicity = they can be lethal in overdose
SO used in treatment of neuropathic pain where smaller doses are typically required

Question 9

What are the different types of TCAs?

Answer 9

[-line, -mine] { & a -pin and a -done}
The more sedative types are:
Amitriptaline
Clomipramine
Dosulepin
Trazodone 
The less sedative types:
Imipramine 
lofepramine
nortriptyline

Question 10

What are the common side effects of TCAs?

Answer 10

Think of anticholinergic effects:

• Urinary retention (–> overflow incontinence due to the anti-Ach = frequent leaking)
• drowsiness (some are more sedative than others)
• dry mouth
• blurred vision
• constipation

& QT interval lengthening!

Question 11

How do you manage neuropathic pain?

Answer 11

low-dose amitriptyline

Question 12

what else is low dose amitriptyline commonly used for other than neuropathic pain?

Answer 12

tension and migraine headache prophylaxis

Question 13

How do benzodiazepines work?

Answer 13

Benzos enhance the effect of inhib neurotransmitter GABA -
Unlike other positive allosteric modulators that increases ligand binding e.g. barbiturates increase the duration of chloride channel opening while, benzodiazipines increase the frequency of chloride channels - benzodiazepine binding acts as a positive allosteric modulator by increasing the total conduction of chloride ions across the neuronal cell membrane when GABA is already bound to its receptor. This increased chloride ion influx hyperpolarizes the neuron’s membrane potential. As a result, the difference between resting potential and threshold potential is increased and firing is less likely.

Question 14

What are benzodiazepines used for?

Answer 14

• Sedation
• Sleep (hypnotic)
• Anxiolytic
• anti-convulsant
• muscle relaxant

Question 15

How long should benzodiazepines be prescribed for?

Answer 15

only a short period ~2-4 weeks
due to patients developing a tolerance (need more to work) and dependence (cluster of physiological, behavioral and cognitive syx where the substance use takes higher priority than other behaviors that once had greater value to them)

Question 16

What are signs of benzodiazepine withdrawal syndroms? (too fast a withdrawal from benzos) - this may occur up to 3 weeks after stopping a long acting drug, features including

Answer 16

Is similar to alcohol withdrawal syndrome:

cant sleep, irritable, anxious, tremor, loss of appetite, tinnitus, sweating, perceptual disturbances, seizures.

Question 17

how should benzos be withdrawn?

Answer 17

Withdraw in steps of about 1/8 of the daily dose every fortnight. The suggested protocol for patients experiencing difficulty is: switch to equivalent diazepam dose and reduce dose every 2-3 weeks in steps of 2 or 2.5mg
Time needed for withdrawal can vary from 4 weeks - >1yr

Question 18

what is aripiprazole used for?

Answer 18

antipsychotic used in schizophrenia treatment and for manic phase of bipolar disorder

Question 19

What is the mechanism of alcohol withdrawal?

Answer 19

chronic alcohol consumption enhances GABA mediated inhibition in the CNS (similar to benzodiazepines) and inhibits NMDA-type glutamate receptors
alcohol withdrawal is thought to be lead to the opposite (decreased inhibitory GABA and increased NMDA glutamate transmission)

Question 20

what is delirium tremens?

Answer 20

medical emergency with onset ~48 hours into abstinence:
gross tremor, confusions, delusions, auditory and visual hallucinations e.g. animals and people, fever, tachycardia (and other autonomic disturbance e.g. sweating , HTN, dilated pupils)

Question 21

when do the features of alcohol withdrawal start?

Answer 21

symptoms start at 6-12 hours: tremor, sweating, tachycardia, anxiety
peak incidence of seizures at 36 hours

Question 22

What is the management of delirium tremens?

Answer 22

first-line: benzodiazepines e.g. chlordiazepoxide. Lorazepam may be preferable in patients with hepatic failure. Typically given as part of a reducing dose protocol
carbamazepine also effective in treatment of alcohol withdrawal
phenytoin is said not to be as effective in the treatment of alcohol withdrawal seizures