CNS Flashcards
According to the Maudsley guidelines, how long does it take before antidepressants exert their effects?
1-2weeks
What are the risk factors for antidepressant-induced hyponatraemia?
Old age Female sex Low body weight Low baseline sodium concentration Some drug treatments (e.g. diuretics, NSAIDs, carbamazepine, chemotherapy) Reduced renal function Medical co-morbidity (e.g. hypothyroidism, diabetes, COPD, hypertension, head injury, CVA, various cancers) Warm weather (summer)
What are the five steps to better wellbeing?
Connect Be active Keep learning Give Take notice
What is the aetiology of depression?
Genetics Environment Biochemistry Endocrine factors Physical illness ADRs
What are the two core screening questions used for depression?
During the last month have you often been bothered by feeling down, depressed or hopeless?
Do you have little interest or pleasure in doing things?
What are the typical symptoms of depression?
Fatigue/loss of energy
Worthlessness/excessive or inappropriate guilt
Recurrent thoughts of death, suicidal thoughts, or actual suicide attempts
Diminished ability to think/concentrate or indecisiveness
Psychomotor agitation or retardation
Insomnia/hypersomnias
Significant appetite and/or weight loss
Define subthreshold depression
Where there is more than 2 but less than 5 symptoms of depression
Define persistent subthreshold depression
Dysthymia, patient has had at least 2 years of depressed mood on more days than not and has at least 2 but less then 5 symptoms
Define mild depression
Few, if any, symptoms in excess of the five required to make the diagnosis, and only minor functional impairment
Define moderate depression
Symptoms or functional impairment between mild and severe. Some symptoms would be expected to be marked
Define severe depression
Several symptoms in excess of those required to make the diagnosis. Some symptoms would be expected to be severe and markedly interfere with functioning
Give an example of a tricyclics antidepressant
Amitriptyline
What are the main ADRs associated with TCAs?
Sedation, postural hypotension, tachycardia/arrhythmia, dry mouth, blurred vision, constipation, urinary retention
What are the major interactions associated with TCAs?
SSRIs (except citalopram), phenothiazines, cimetidine, alcohol, antimuscarinics, antipsychotics, MAOIs
Give an example of an SSRI
Citalopram
What are the main ADRs associated with SSRIs?
Nausea, vomiting, dyspepsia, abdominal pain, diarrhoea, rash, sweating, agitation, anxiety, headache, insomnia, tremor, sexual dysfunction, hyponatraemia, cutaneous bleeding disorders
What SSRIs are used in panic disorder?
Citalopram, escitalopram, paroxetine
What SSRIs are used in agoraphobia?
Citalopram, escitalopram, paroxetine
What SSRIs are used in social anxiety?
Escitalopram and paroxetine
What SSRIs are used in GAD?
Escitalopram and paroxetine
What SSRIs are used in OCD?
Escitalopram, fluoxetine, fluvoxamine, sertralineline
What interactions are associated with SSRIs?
MAOIs, lithium
What cautions surround the use of SSRIs?
Patients under 18
Epilepsy
What are the contraindications for the use of SSRIs?
Mania
What cautions surround the use of TCAs?
Depression associated with suicidal thoughts
Epilepsy
Give an example of an SNRI
Venlafaxine, duloxetine
What ADRs are associated with SNRIs?
Nausea, HTN, serotonin syndrome
What cautions surround the use of SNRIs?
Epilepsy
HTN
MI
What interactions are associated with SNRIs?
MAOIs
What class of drug is mirtazapine?
Presynaptic alpha-2 adrenoceptor blocker
What ADRs are associated with mirtazapine?
Drowsiness Weight gain Fatigue Tremor Dizziness
What class of drug is trazodone?
Serotonin receptor blocker
What ADRs are associated with MAOIs?
Dose-related postural hypotension
What interactions are associated with non-selective MAOIs?
Amine-containing drugs including sympathomimetics and tyramine
What ADRs are associated with reversible MAOIs?
Sleep disturbance Agitation Confusion GI upset Dizziness Headache
What are the symptoms of serotonin syndrome?
Confusion Hypomania Agitation Twitching Tremor Hyperthermia Sweating Shivering Diarrhoea HTN CV collapse
What drugs cause serotonin syndrome?
SSRIs Serotonin precursors (tryptophan) Serotonin agonists (triptans, buspirone, LSD) Serotonin releasing agents (ecstasy, amphetamines) MAOIs Chlorphenamine Pethidine Cocaine Tramadol Levodopa Bromocriptine Lithium St John’s wort
How does hypertensive crisis occur?
MAOIs reduce breakdown of NA in adrenergic nerve ending
=> large stores that can be released into synaptic cleft in response to a neuronal discharge or an indirectly acting amine
What are the symptoms of hypertensive crisis?
HTN
Headache
Hyperpyrexia
Cardiac arrhythmias
How is hypertensive crisis managed?
Alpha-blockade with phentolamine
Describe the aetiology of anxiety
Stress Genetics Drugs Withdrawal Metabolic disturbances Temporal lobe lesions Rare hormone-secreting tumours e.g. phaeochromocytoma
What are the clinical features of anxiety?
Apprehension and fear
Somatic symptoms: palpitations, chest pain, SOB, dizziness, loss of libido, headaches, tremor
Describe the mechanism of action of benzodiazepines
Selective agonist on GABAa receptors, enhance responses to GABA by facilitating the opening of GABA-activated chloride channels, inhibit neuronal excitability
What ADRs are associated with benzodiazepines?
Respiratory distress and arrest Sedation/drowsiness Ataxia Confusion and amnesia Tolerance and dependence
What cautions surround the use of benzodiazepines?
Liver disease
Avoid alcohol
Avoid in pregnancy
What are the contraindications for the use of benzodiazepines?
Respiratory depression
Myasthenia gravis
What interactions are associated with benzodiazepines?
CNS depressants
Erythromycin, ketoconazole, fluconazole
What advice can be provided for benzodiazepine withdrawal?
Avoid prolonged treatment (<4w)
Gradual withdrawal over 4-8 weeks is desirable
Switch to a longer acting benzo
Dose reduction 2mg diazepam equivalents every 2w
What are the effects of benzodiazepine toxicity?
Excessive sedation, respiratory depression, coma
What is the treatment for benzodiazepine toxicity?
Romazicon (flumazenil) 0.2mg over 30s, wait 30s, 0.3mg over 30s, then 0.5mg every 60s up to a maximum of 3mg
What class of drug is buspirone?
5HT1a partial agonist
What ADRs are associated with buspirone?
Nausea
Dizziness
Headache
Restlessness
What ADRs are associated with z-drugs?
Drowsiness
Headache
Weakness
Dizziness
What cautions surround the use of z-drugs?
Confusion
Dependence
What are the contraindications for the use of z-drugs?
Respiratory insufficiency
Sleep apnoea
Myasthenia gravis
What are the symptoms of Alzheimer’s disease?
Memory loss Language difficulties Problems with visuospatial skills Difficulties with organisational skills Difficulties with orientation Confusion Hallucinations Delusions
What are the symptoms of vascular dementia?
Apraxia
Slurred speech
Dizziness
Inability to recognise familiar objects
What are the symptoms of DLB?
Confusion Attention deficits Problems with executive functions Visuospatial disturbances Hallucinations Repeated falls Syncope Transient, unexplained loss of consciousness Severe autonomic dysfunction Non-visual hallucinations Depression REMS disorders
What are the symptoms of behavioural variant frontotemporal dementia?
Loss of inhibitions Loss of motivation Loss of sympathy or empathy Craving sweet or fatty foods Develop compulsions Difficulty planning, organising or making decisions Lack of insight into their symptoms
What are the symptoms of progressive non-fluent aphasia?
Slow, hesitant speech
Difficulties with grammar
Difficulties understanding complete sentences
What are the symptoms of semantic dementia?
Asking the meaning of familiar words
Difficulty finding the right word or use of generalised words
Difficulty recognising familiar people or common objects
What class of drug is rivastigmine, donepezil and galantamine?
Acetylcholinesterase inhibitor
How do acetylcholinesterase (AChE) inhibitors work?
Block breakdown of acetylcholine, compensating for the loss of cholinergic neurones
What ADRs are associated with AChEIs?
Miosis Nausea Vomiting Bronchoconstriction Salivation Sweating Urinary incontinence Alertness Agitation Hallucination Dizziness Insomnia Seizures Bradycardia SA and AV block Pain Headache Muscle cramps
What class of drug is memantine?
Glutamate receptor antagonist
What ADRs are associated with memantine?
Constipation HTN Dizziness Tiredness Headache Vomiting Hallucinations Confusion Seizures
What antipsychotic is licensed in treatment of BPSD?
Risperidone
