MENTAL HEALTH DRUGS Flashcards
give an example of a benzodiazepine
Diazepam, lorazepam, oxazepam
what is the structure and pathophysiology of benzodiazepines?
It contains benzoring
Acts on the GABAa receptor increasing the inhibitory neurotransmitter effects by opening the chloride channel( gaba receptor) and increase chloride movement into the cells
Which causes inhibitor of the cells to depolarize
What conditions are BZDP used for?
- Short term for severe, disabling or distressing Anxiety
- Short term for severe, disabling or distressing Insomnia
- First line for seizure and status epilepticus
- 1st line for alcohol withdrawal
- premedication for procedures + agitation
when would you give buccal midazolam
seizure emergency
why shouldn’t BZDP’s be given in myasthenia graves, sleep apnoea, bronchitis or COPD?
can cause respiratory depression
why shouldn’t BZDP’s be given to a patient with liver failure?
Increase chance of hepatic encephalopathy
why shouldn’t BZDP’s be given in patients with renal failure?
Increased cerebral sensitivity to the drug
what is the antidote for BZDP overdose?
flumazenil
give 3 complications of taking BZDP’s in pregnancy
cleft palate
floppy infant syndrome
neonatal withdrawal syndrome
what effect can BZDP’s have on the circulation?
Hypotension and hypovolaemia
how are BZDP’s metabolised?
cytochrome P450
what 2 things can potentiate action of BZDP’s?
alcohol
opiates
give an example of an acetylcholinesterase inhibitor
donepezil, rivastigmine and galantamine
how do ACh-E inhibitors work?
Inhibits the acetylcholinesterase enzyme from breaking down acetylcholine,–> increasing the level and duration of action of the neurotransmitter acetylcholine on the synapse .
when are ACh-E inhibitors used?
mild to moderate treatment of alzheimer’s and Parkinsons ( non cognitive symptoms)
give 2 cardiac contraindications for ACh-E inhibitors
heart disease
arrhythmias
give 2 respiratory contraindications for ACh-E inhibitors
asthma
COPD
give 2 GI contraindications for ACh-E inhibitors
peptic ulcer disease
NSAIDs
(they increase risk of peptic ulcer disease)
how do ACh-E inhibitors interact with bentropine/atropine/trihexyphenidyl?
anticholinergic drugs- reverse action
give an example of a TCA
amitriptyline, doxepin, lofepramine and imipramine
TCA’s inhibit reuptake of what? How long do they take to work?
serotonin and noradrenaline and therefore more neurotransmission activity
Take 2-4 weeks to work
when are TCA’s used?
depression= second line treatment
Unlicensed for neuralgia, panic disorder and migraine
What is the interaction of TCA and MAO’s?
Both increase the levels of noradrenaline and serotonin which can cause precipitation of hypertension, hyperthermia and serotonin syndrome
Due to the antimuscarinic effects of TCA who should it be cautiously used for?
cautious in patients with prostatic hypertrophy, chronic constipation, increased intra-ocular pressure, urinary retention, or those with a susceptibility to angle-closure glaucoma.
give a cardiovascular side effect of TCAs
ECG changes
Arhythmia= Increase QR and QRS
Increase risk of MI and stroke
What are the antimuscarinic side effects of TCA?
Constipation
dry mouth
urinary retention and blurred vision
what is the metabolism of TCAs?
cytochrome P450
why shouldn’t TCAs be given with anticholinergics?
increase risk of paralytic ilius
give an example of an SSRI
citalopram, setryline, flouxetine and fluvoxamine
how do SSRIs work?
inhibit neuronal uptake of serotonin (5-ht)
give 2 examples of when SSRIs are used
Moderate to severe depression
Mild depression if physiological treatment not worked
OCD
Panic disorder
use of SSRIs with MAOIs increases the risk of what syndrome?
serotonin syndrome
why should SSRIs be used with caution with other CNS drugs
can interfere with CNS due to central action
how do SSRIs interfere with NSAIDs, aspirin and warfarin?
interfere w homeostasis and can cause upper GI bleed.
Need gastroprotection
For what condition is benzodiazepine
a) short acting
b) long acting
a) insomnia
b) anxiety
Which one of these is not a route for benzodiazepine
a) IV
b) IM
c) rectal
d) buccal
e) oral
oral
What is BZDP used for?
Anxiety
Insomnia
Seizures and muscle spasm
Alcohol withrawel
Except for circulation side effects what other side effects does BZDP have?
Dependancy and withdrawel symptoms
Loss of airway reflex leading to airway closure and death
Dose dependent drowsiness, sedation and coma
How is ACETYLCHOLINESTERASE INHIBITORS administrated?
Oral–> daily
What MSK symptom do you get in using ACh-E inhibitors
Muscle cramps
How is ACh-E inhibitors metabolised?
Cytochrome p450
What drugs reduce the effects of ACH-E inhibitor?
Dexemathasone, rifampicin, ACh-E inhibitors, carbamazepine
What type of rash do you get with hypersensitivity to TCA?
Urticaric rash
What is serotonin syndrome?
Triad of:
Autonomic hyperactivity
Neuromuscular excitation
Altered mental state
What affect does SSRi’s have on patients with epilepsy?
Increase the chance of a seizure and they reduce the threshold for seizures
Why is it important not to give SSRI’s to a patient especially elderly if they are hyponatraemia?
Increase the risk of confusion and reduced consciousness
How does SSRI’s increase the risk of bleeding?
They increase the risk of peptic ulcer diseases
Why should the use of SSRI’s with young adults be used cautiously?
Low efficiency and increase the incidents of self harm and suicide thoughts
What are common adverse effects of SSRI’s?
GI distrubance, weight and appetite change and hypersensitivity reaction
What ECG changes may you see in someone taking SSRI’s?
Increase QT interval
What drug should SSRI’s not be combined with due to excessive increase of QT interval?
Antipsychotics.
What are the side effects of sudden withdrawal of SSRI’s or TCA?
GI upset, neurological and influenza like symptoms and sleep disturbance
Which drug is preferred SSRI’s or TCA and why?
SSRI’s due to less adverse effects and less danger of overdose
which of these is not an effect of diazepines?
a) sedative
b) hypnotic
c) spasmodic
d) muscle relaxant
e) anticolvulsant
c) spasmodic
why shouldn’t BZDP’s be given in major depression?
can precipitate suicidal thoughts
What should happen to the dose when giving BZDP to elderly patient?
Reduced dose
How is Acetycholinesterase inhibitor metabolised?
By p450
Should TCA be used after immediate recovery period of MI?
No
What are the acute withdrawel symptoms of TCA?
gastrointestinal upset, neurological and influenza-like symptoms and sleep disturbance.
What side effects can TCA have on the brain?
Hallucinations
Convulsions
mania
What is the side effects of TCA overdose?
Severe hypotension Arrhythmias Convulsions Respiratory failure Coma
