Psychopharmacology Flashcards
What is the therapeutic window for lithium?
0.4-0.8 (or 1.0) mmol/L
What is there a marked increased risk of to the baby if lithium is taken during pregnancy?
Ebstein’s anomaly - a right ventricular outflow tract obstruction defect
How does lithium toxicity present? (4)
- Increased drowsiness
- Blurred vision
- GI upset - anorexia, vomiting
- Ataxia, coarse tremor
If lithium levels are >2mmol/l, what are the symptoms of severe toxicity? (4)
- Convulsions/hyperreflexia
- Renal failure
- Coma
- Death
What is the treatment of lithium toxicity?
- Hospitalise
- Stop lithium
- Check lithium levels
- Give fluids
5.
What are the alternatives to lithium? (other mood stabilisers)
- Sodium valproate
- Carbamazepine (auto induction?)
- Lamotrigine
What is the problem with switching to sodium valproate from lithium?
Hepato toxic
If a woman is planning to get pregnant/is pregnant, what is a safer drug to take rather than lithium for their bipolar disorder/depression resistant to treatment?
Antipsychotics - can function as mood stabilisers and are relatively safer in pregnancy -
1. Olanzepine
2. Haloperidol
(small dose and regular monitoring)
What is rapid tranquillisation?
- short term immediate treatment usually IM under restraint, due to highly agitated and aggressive behaviour
1. Protocol for controlling disturbed behaviour
2. Verbal methods should be tried first
3. Lorazepam 1mg +/- haloperidol 5mg (widely used, normally benzodiazepine is not enough, cannot give olanzapine and lorazepam together within an hour of each other)
A patient who was given IM rapid tranquillisation and who is on regular antipsychotics, experiences stiffness and slow movements, what is the cause of this?
Side effects of antipsychotic on the nigrostriatal pathway, blocking the dopamine receptors. It causes the parkinson-like side effects:
-Pseudo-parkinsonism
-Akathisia (inner restlessness)
-
How do you detect the side effects of antipsychotics?
Examine:
- Gait
- Tremor
- Restlessness
- test elbow rigidity
- finger/thumb tap test
Other side effects of antipsychotics in addition to parkinsonism?
Antimuscarinic - dry mouth, urinary retention
Antiadgrenergic
Antihistamine
What is neuroleptic malignant syndrome? (6)
Very rare (0.2%) and rapid onset of: 1. Stiffness 2. Impaired consciousness 3. Hyperpyrexia 4. Unstable blood pressure 5. CPK levels elevated 6. 10% mortality (immediately take a temperature to assess and send a blood test for creatinine kinase)
What do you need to consider if someone has treatment resistant schizophrenia?
- Compliance
- Co-morbidities - drugs?
- Correct diagnosis?
Which drug can be given for treatment resistant schizophrenia? (where they have tried two or more atypicals?)
Clozapine
What are the side effects of clozapine? (7)
- Agranulocytosis (1%)
- Blood tests (every week for the first 18 weeks)
- Drowsiness
- Constipation
- Hyper-salivation
- Hypotension
- Cardiomyopathy
Which two neurotransmitters is there a shortage of in depression?
Serotonin
Noradrenaline
What are the side effects of SSRIs? (8)
- Nausea
- Diarrhoea
- Sleep disturbance
- Anxiety
- GI bleeds
- Withdrawal effects
- Suicidality
- QTc? - SAD HART research
What are the side effects of TCAs?
- Block Ach muscarinic receptors - dry mouth, urinary retention
What foods must be avoided in someone taking MAOI? (6)
- Avocado
- Herring
- Meat extracts
- Cheese
- Beer
- Flavia beans
What can you do with treatment resistant depression?
- Check this is the correct diagnosis
- Exclude physical causes
- High enough dose, long enough time?
- Switch to new class e.g. SNRI/TCA/MAOIs
- Augment - lithium for a short time or antipsychotics
- ECT
Which medication is required for a patient suffering from severe side effects of his anti-psychotic. The side effects include repetitive involuntary side effects such as grimacing and sticking out the tongue.
Tetrabenazine - this patient is suffering from tardive dyskinesia and as the episode is described as severe, this is the most appropriate.
What drug is used to treat the side effect of akathisia (restlessness) as a result of anti-psychotics?
Propanolol
Which medication is used to treat acute dystonia, a side effect of anti-psychotics?
Procyclidine and benztropine
Which SNRI is most appropriate to prescribe for generalised anxiety disorder?
Venlafaxine
Which antidepressants are recommended during pregnancy? (3)
- Fluoxetine
- Amitriptyline
- Imipramine
Which antidepressants are recommended in breastfeeding? (2)
- Paroxetine
2. Sertraline
What is important to tell patients when starting them on antidepressants?
- Although they are not a solution to all the problems that may be co-existing/coinciding, they can lift your mood and give you a better chance of addressing them
- Antidepressants are effective in over 60% of patients, but it can be 10-20 days before you start to notice an effect, better sleep is often the first sign of improvement
- Antidepressants may have troublesome side effects, but these tend to resolve in the first mont of treatment
- Antidepressants should not be stopped suddenly once treatment is established
What is the response rate to SSRIs?
55-70%
What are the side effects of SSRIs? (7)
- Dry mouth
- Nausea
- Vomiting
- Diarrhoea
- Dizziness
- Agitation
- Sexual dysfunction
Which SSRIs are inhibitors of CYP450 enzymes?
Fluoxetine and paroxetine
What is the SSRI discontinuation syndrome?
This consists of headache, dizziness, shock-like sensations, paraesthesia, lethargy, insomnia, mood changes.
TCAs inhibit the re-uptake of which two neurotransmitters?
- Serotonin
2. Noradrenaline
What are the principle side effects of TCAs? (4 groups - lots of side effects)
- Anticholinergic = dry mouth, blurred vision, constipation, urinary retention
- Antihistaminergic = weight gain, sedation
- Cardiotoxic = arrhythmias (prolonged QT, ST/T changes)
- Neurotoxic = delirium, convulsions
Why are MAOIs less commonly used?
Monoamine oxidise inhibitors are associated with the tyramine reaction - a hypotensive crisis that can result in a SAH. They have to adhere to a strict diet and avoid tyramine containing food produce including cheese and others things… ‘cheese and chianti’
What are the short term side effects of lithium? (7)
- Fine tremor
- GI disturbances
- Muscle weakness
- Polyuria
- Polydipsia
- Coryza symptoms
- Metallic taste in mouth
What are the long term side effects of lithium? (8)
- Weight gain
- Oedema
- Goitre
- Hypothyroidism
- Hyperparathyroidism
- Nephrogenic diabetes insipidus
- Irreversible renal damage
- Cardiotoxicity - T wave flattening
Which drugs can interact with lithium?
- Diuretics
- Carbamazepine
- NSAIDs
- ACE inhibitors
Which anti-convulsant is first-line in the adjuvant treatment of BAD - especially if it is a rapid-cycling BAD, as it has a quick onset?
Valproate
What are the side effects of valproate? (7)
- Nausea
- Tremor
- Sedation
- Weight gain
- Alopecia
- Hepatotoxicity
- Pancreatitis
What is the psychological treatment for BAD? (3)
- Education about the symptoms, course and treatment of the disorder
- Importance of drug compliance
- Advice about lifestyles
Lots of patients with severe mental health and physical problems can become malnourished due to self-neglect, and for some, re-feeding syndrome can occur when they are admitted to hospital. What happens in re-feeding syndrome?
- The malnourishment results in depletion of phosphate, potassium, magnesium and glucose
- Depletion of phosphorus leads to problems with breathing and energy supply due to it being required for oxygen transport around the body, it affects almost every physiological system due to the intracellular processes it involves and the structural integrity of the cell membrane
- As a result of re-feeding syndrome insulin causes potassium to move intracellularly resulting in severe hypokalaemia - arrhythmias
- Magnesium deficiency follows the same pattern as potassium and depletion causes neuromuscular complications
- Glucose in re-feeding stimulates the release of glucose and stops gluconeogenesis from happening, but the constant supply of glucose can lead to hyperglycaemia as metabolism has decreased so much, leading to dehydration, metabolic acidosis and ketoacidosis.
- Thiamine deficiency - Wernicke’s encephalopathy
- Sodium, nitrogen and fluid leads to a decrease in sodium excretion which leads to water retention and oedema
Which particular patients are at high risk of re-feeding syndrome?
- Anorexia nervosa
- Chronic alcoholism
- Dysphagia patients
- Older people
- Chronic malnutrition
What are the side effects of anti-psychotics? (13)
- Extrapyramidal symptoms
- Hyperprolactinaemia (amenorrhoea, loss of libido, gynaecomastia in men)
- Neuroleptic malignant syndrome
- Weight gain (increased appetite)
- Anxiety
- Insomnia
- Hypercholesterolaemia
- Diabetes
- Tachycardia
- Dry mouth
- Blurred vision
- Constipation
- Urinary retention
What are all the symptoms of hyperprolactinaemia? (6)
- Loss of libido
- Amenorrhoea
- Erectile dysfunction
- Galactorrhoea
- Gynaecomastia
- Reduced bone density
What are the extra pyramidal side effects seen in anti-psychotic medications? (4)
- Acute dystonia (spastic contractions)
- Akathisia (inner restlessness)
- Parkinson-like symptoms - tremor, muscle rigidity, bradykinesia
- Tardive dyskinesia - involuntary, repetitive, purposeless movements (tics) ‘rabbit syndrome’
What is medicines reconciliation?
is the process of identifying an accurate list of persons current medicines and comparing the with the current list in use, recognising any discrepancies, and documenting any chances, thereby resulting in a complete list of medicines, accurately communicated.
What does glutamate do? ..in simple terms..
Turns the brain on: builds memory, regulates alertness, movement, sensation and mood
What does GABA do? ..in simple terms..
Turns the brain off: involved in sleep, sedation, relaxation, reducing anxiety, decreasing muscle tension
What do endocannabinoids do?
Regular pain, appetite, coordination and learning
What does serotonin do?
Regulates mood, anxiety, appetite, sleep/wake cycle and body temperature
What does noradrenaline do?
Creates feelings of alertness, attention, concentration, raises blood pressure, lifts mood and can increase anxiety
What does dopamine do?
Creates feelings of motivation and drive, liking, attention, pleasure, and enjoyment of food
What does acetylcholine do?
Regulates sleep/wake cycle, alertness and memory
What does adenosine do?
Makes us feel tired and hungry
What do endorphins do?
Create feelings of pleasure and reward, reduce pain
What does substance P do?
Regulates pain and stress response
What does cholecystokinin do?
Tells us when to eat, possibly involved in managing anxiety
Which one of the chemical neurotransmitters is a lipid?
Endocannabinoids
Which of the neurotransmitters have on/off switches? (2)
Glutamate and GABA
Which neurotransmitters does alcohol act on? (2)
- GABA agonist
2. Glutamate antagonist
Which neurotransmitter do benzodiazepines work on?
GABA agonist
Which neurotransmitter does ketamine act on?
Blocks glutamate
How does caffeine work?
Antagonist at adenosine A2 receptor - reduces sedation and increases noradrenaline
Which neurotransmitter does cannabis work on?
Endocannabinoid signalling - leading to change in cortical and memory functions
Which neurotransmitter do amphetamines act on?
They lead to the release of dopamine and block its re-uptake
Which neurotransmitters does MDMA effect?
Blocks serotonin and dopamine re-uptake
Which receptors do heroin and other opioids act on?
Endorphin receptors - produce euphoria and reduces pain
What is the COWS assessment used for?
It stands for clinical opiate withdrawal scale, and is used to assess the extent to which the individual is affected
What are the symptoms used in the COWS assessment? (11)
- Heart rate
- Sweating
- Restlessness
- Pupil size
- Bone or joint aches
- Runny nose or tearing
- GI upset
- Tremor
- Yawning
- Anxiety and irritability
- Gooseflesh skin
What are the signs of an overdose from a CNS depressant?
- Shallow breathing
- Weak pulse
- Clammy skin
- Coma
- Respiratory arrest
What are the signs of an overdose of a hallucinogen?
- Psychotic features
- Agitation
- Delirium
What are the signs of an overdose of cannabis?
- Drowsiness
- Unsteady gait
- Vomiting
- Tachycardia
- Agitaiton
- Psychosis
Summarise neuroleptic malignant syndrome?
NMS is a life-threatening neurological condition that can occur with the use of typical or atypical antipsychotics, particularly occurring after an increase in dose. Symptoms include pyrexia, fluctuating consciousness, muscle rigidity and autonomic dysfunction.
Investigations will reveal a raised creatine kinase, raised WCC, and abnormal LFTs.
What is the treatment for NMS?
Stop the offending drug, fluid resuscitation and sometimes dantrolene is used to treat muscle spasm (or possibly baclofen), and bromocriptine to reverse dopamine blockade.
What are the signs of serotonin syndrome? (6)
- Severe hypetension
- Tachycardia
- High pyrexia
- Myoclonus
- Sweating
- Hyper-reflexia
Which drugs are used to manage acute episodes of mania?
Neuroleptics - olanzapine or haloperidol