CHAPTER 4 – CENTRAL NERVOUS SYSTEM
4.1 HYPNOTICS AND ANXIOLYTICS
Temazepam short acting, therefore good for dental
Short acting Benzodiazepines have greater risk withdrawal symptoms
Hepatic impairment use short acting e.g. Lorazepam
BNZ CONTRAINDICATED: Respiratory depression, pulmonary depression, myasthenia gravis
Paradoxical effects (hostility and aggression)
Diazepam had a long T½, so avoids sharp fluctuations in plasma levels, so less likely to get withdrawal with
late dose
When withdrawing from BDZs, convert dose to Diazepam dose and then withdraw patient slowly
Buspirone: 5HT1A antagonist, used for anxiety
4.2 DRUGS USED IN PSYCHOSES AND RELATED DISORDERS
4.2.1 Antipsychotic Drugs
Tranquillise without impairing consciousness
SIDE EFFECTS: EPSEs
Typical Antipsychotics (more EPSEs), Atypical are thought to be more safe
Clozapine
o SIDE EFFECTS: Myocarditis, cardiomyopathy, agranulocytosis (Blood tests required)
4.2.2 Antipsychotic Depot Injections
Given at intervals of 1-4 weeks.
4.2.3 Antimanic Drugs
Carbamazepine
o SIDE EFFECT: Blood dyscrasias
Valporic Acid
Lithium
o Toxicity d by Na+ depletion therefore avoid thiazides
o Must stick to the same brand
o Should avoid major dietary changes, esp with salt
o LONG TERM HAS BEEN ASSOCIATED WITH Thyroid disorders, mild cognitive and memory impairment
4.3 ANTIDEPRESSANT DRUGS
Choice of Antidepressant (AD)
o SSRIs are 1st choice in depression
Better tolerated and safe in OD
CAUTION IN ELDERLY: CSM: Hyponatreamia should report signs such as confusion,
drowsiness or convulsions
COUNSELLING: Cause insomnia so should take in the morning
SIDE EFFECT OF FLUOXETINE: EPSEs reported
o TCAs have similar efficacy to SSRIs, but are not as well tolerated due to S/E
Dangerous in OD Cardiotoxicity
o MAOIs – dangerous interactions with food (S&S = throbbing headache)
4.1 HYPNOTICS AND ANXIOLYTICS
Temazepam short acting, therefore good for dental
Short acting Benzodiazepines have greater risk withdrawal symptoms
Hepatic impairment use short acting e.g. Lorazepam
BNZ CONTRAINDICATED: Respiratory depression, pulmonary depression, myasthenia gravis
Paradoxical effects (hostility and aggression)
Diazepam had a long T½, so avoids sharp fluctuations in plasma levels, so less likely to get withdrawal with
late dose
When withdrawing from BDZs, convert dose to Diazepam dose and then withdraw patient slowly
Buspirone: 5HT1A antagonist, used for anxiety
4.2 DRUGS USED IN PSYCHOSES AND RELATED DISORDERS
4.2.1 Antipsychotic Drugs
Tranquillise without impairing consciousness
SIDE EFFECTS: EPSEs
Typical Antipsychotics (more EPSEs), Atypical are thought to be more safe
Clozapine
o SIDE EFFECTS: Myocarditis, cardiomyopathy, agranulocytosis (Blood tests required)
4.2.2 Antipsychotic Depot Injections
Given at intervals of 1-4 weeks.
4.2.3 Antimanic Drugs
Carbamazepine
o SIDE EFFECT: Blood dyscrasias
Valporic Acid
Lithium
o Toxicity d by Na+ depletion therefore avoid thiazides
o Must stick to the same brand
o Should avoid major dietary changes, esp with salt
o LONG TERM HAS BEEN ASSOCIATED WITH Thyroid disorders, mild cognitive and memory impairment
4.3 ANTIDEPRESSANT DRUGS
Choice of Antidepressant (AD)
o SSRIs are 1st choice in depression
Better tolerated and safe in OD
CAUTION IN ELDERLY: CSM: Hyponatreamia should report signs such as confusion,
drowsiness or convulsions
COUNSELLING: Cause insomnia so should take in the morning
SIDE EFFECT OF FLUOXETINE: EPSEs reported
o TCAs have similar efficacy to SSRIs, but are not as well tolerated due to S/E
Dangerous in OD Cardiotoxicity
o MAOIs – dangerous interactions with food (S&S = throbbing headache)
