Mental illness Flashcards
How many types of antipsychotic medications are there?
Two types:
1. ‘first generation’ (older; typical) antipsychotics
2. ‘second generation’ (newer; atypical) antipsychotics
Common indications for 1st generation antipsychotics?
Severe psychomotor agitation
Schizophrenia
Bipolar disorder (particularly in acute episodes of mania or hypomania)
Nausea and vomiting (particularly in palliative care setting)
What is the mechanism of action for 1st generation antipsychotics?
Blocks post-synaptic dopamine D2 receptors in the following pathways:
- mesolimbic (ML)
- mesocortical (MC)
- nigrostriatal (N)
- tuberohypophyseal (T)
How are 1st generation antipsychotics further classified?
High potency -strong antipsychotic effect at low dose
Low potency -does not tightly bind to D2 receptors and can affect other receptors (e.g. alpha-adrenergic, cholinergic, histamine receptors)
Examples of high potency 1st generation antipsychotics?
Haloperidol
Fluphenazine
Prochlorperzine
Trifluoperazine
Examples of low potency 1st generation antipsychotics?
Chlorpramazine
What are the important adverse effects of 1st generation antipsychotics?
Extrapyramidal effects (impaired motor control; N pathway affected)
- acute dystonic reactions such as involuntary parkinsonian movements or muscle spasms
- akathisia (inner restlessness)
- neuroleptic malignant syndrome (rare, but life-threatening; involves rigidity, confusion, autonomic dysregulation, pyrexia)
- tardive dyskinesia (late adverse effect; involves involuntary and repetitive movements)
Drowsiness
Hypotension
QT-interval prolongation (and consequent arrhythmias)
Erectile dysfunction
Hyperprolactinaemia (due to D2 receptors blocked in T pathway; menstrual disturbance, galactorrhoea, breast pain)
Warnings of 1st generation antipsychotics?
Elderly -sensitive to antipsychotics, hence start with lower dose.
Avoid in dementia -increased risk of death and stroke
Avoid in Parkinson’s disease -due to extrapyramidal effects (links to SEs)
Important interactions of 1st generation antipsychotics?
Any drugs that prolong the QT interval (e.g. amiodarone, macrolides)
There are many drugs that interact with antipsychotic drugs, so refer to BNF.
How are 1st generation antipsychotics monitored?
Review pt for control of symptoms and signs.
May take several wks for the drug effects to establish and reach the optimum balance of beneficial and adverse effects.
Response to high doses for acute control of psychotic/violent behaviour is unpredictable, so monitor for neurological, respiratory and cardiovascular effects.
How would you explain to the pt about taking a 1st generation antipsychotic drug?
Antipsychotic medicines aim to block certain chemicals in the brain to help control symptoms.
It may take several wks to establish its effect.
There are several side effects as with any medication, for e.g. impaired motor control, drowsiness, low blood pressure, and erectile dysfunction.
It is important to inform other healthcare professionals involved in your care because there are many medications that can play a role in how the antipsychotic medicine works.
Which 1st generation antipsychotics is commonly used for 1st line?
Haloperidol
Common indications for 2nd generation antipsychotics?
Severe psychomotor agitation
Schizophrenia
Bipolar disorder (particularly in acute episodes of mania or hypomania)
What is the mechanism of action for 2nd generation antipsychotics?
Blocks post-synaptic dopamine D2 receptors in the following pathways:
- mesolimbic (ML)
- mesocortical (MC)
- nigrostriatal (N)
- tuberohypophyseal (T)
Compared to 1st generation, the 2nd generation antipyschotics are:
- more efficacious in ‘treatment resistant’ schizophrenia
- against negative symptoms
- reduces the risk of extrapyramidal symptoms.
This could be due to higher affinity for other receptors like serotonin 2A receptor and a ‘looser’ binding to D2 receptors (e.g. clozapine, quetiapine).
What are the important adverse effects of 2nd generation antipsychotics?
Sedation
Extrapyramidal effects
Metabolic disturbance (wt gain, DM, lipid changes)
Prolong the QT interval, thus cause arrhythmias
Breast pain, swollen, galactorrhoea (men&women)
Sexual dysfunction
Agranulocytosis (low neutrophil count; clozapine effect)
Myocarditis (rare)
Warnings of 2nd generation antipsychotics?
Caution with cardiovascular disease.
Avoid in severe heart disease or hx of neutropenia.
Important interactions of 2nd generation antipsychotics?
Do not use along side:
- dopamine-blocking antiemetics
- drugs that prolong the QT interval (e.g. amiodarone, quinine, macrolides, SSRIs)
How are 2nd generation antipsychotics monitored?
Monitor symptoms and signs for tx efficacy.
Do b/t (FBC, renal, liver) at the start of tx and every week for 18 weeks, then fortnightly for up to one year, and then monthly.
Must monitor closely if pt is taking clozapine due to risk of agranulocytosis.
Monitor blood lipids and wt at baseline, 3 months, then yearly. Wt should be measured frequently during the first 3 months.
Fasting blood glucose measured at baseline, at 4-6 months, then yearly.
Patients taking clozapine should have fasting blood glucose tested at baseline, after one months’ treatment, then every 4–6 months.
How would you explain to the pt about taking a 2nd generation antipsychotic drug?
Antipsychotic medicines aim to block certain chemicals in the brain to help control symptoms.
It may take several wks to establish its effect.
There are several side effects as with any medication, for e.g. impaired motor control, agranulocytosis, breast symptoms, wt gain, and sexual dysfunction.
It is important to inform other healthcare professionals involved in your care because there are many medications that can play a role in how the antipsychotic medicine works.
If pt is taking clozapine, tell pt they need regular b/t monitoring and they need to report infection symptoms immediately.
How many classes of antidepressants are there?
Five classes:
1. SSRIs (selective seretonin reuptake inhibitors)
2. SNRIs (serotonin/norepinephrine reuptake inhibitors)
3. TCAs (tricyclic antidepressants)
4. MAOIs (monoamine oxidase inhibitors)
5. Atypical antidepressants
Common indications for SNRIs?
Major depression (if 1st line SSRI is ineffective or not tolerated)
Generalised anxiety disorder
Examples of SNRIs?
Venlafaxine
Mirtazapine
What is the mechanism of action for SNRIs?
Venlafaxine
- prevents uptake of serotonin and norepinephrine from the synaptic cleft.
Mirtazapine
- an antagonist of inhibitory pre-synaptic alpha-2-adrenoceptors
Both drugs increase availability of monoamines for neurotransmission, which improves mood and physical symptoms in moderate/severe depression.
What are the important adverse effects of SNRIs?
GI upset:
- Dry mouth
- Nausea
- Wt changes
- Diarrhoea
- Constipation
Neurological effects:
- headache
- abnormal dreams
- insomnia
- confusion
- convulsions
Hyponatraemia (low sodium)
Serotonin syndrome
Suicidal thoughts and behaviour
Ventricular arrhythmia
Sudden drug withdrawal (can cause above symptoms, influenza-like symptoms and sleep disturbance; greater risk when using venlafaxine)
Warnings of SNRIs?
Elderly -risk of adverse effects
Hepatic or renal impairment -reduce dose
Caution in pts at risk of arrhythmias (due to ischaemic heart disease).
Important interactions of SNRIs?
Increase risk of SEs if combining drugs from other antidepressant classes -should be avoided.
How are SNRIs monitored?
Symptoms reviewed 1-2 wks after starting tx and regularly thereafter.
No effect at 4 wks, consider changing dose or drug.
If there is an effect at 4 wks, do not adjust dose until after 6-8 wks of therapy.
How would you explain to the pt about taking a SNRI drug?
SNRI medicines aim to increase certain chemicals (serotonin and norepinephrine) in the brain to help improve symptoms over a few weeks, particularly sleep and appetite.
Must carry on the drug tx for at least 6 months after they feel better. This is to stop the depression from returning. (2 years for recurrent depression).
Warn pt to not stop tx suddenly as it can cause flu-like withdrawal symptoms and sleeplessness. When the time comes to stop tx, the dose will be reduced slowly over 4 wks.
Pts taking mirtazapine, seek medical advice for symptoms of infection (e.g. sore throat), b/t needs to be done to check for blood disorders.
Discuss about referring them for psychological therapy, which may offer more long term benefits than drug treatment.
There are several side effects as with any medication, for e.g. nausea, wt changes, diarrhoea, constipation, headaches, confusion, insomnia, suicidal thoughts and behaviour.
Common indications for SSRIs?
Moderate/severe depression (1st line)
Mild depression (if psychological tx alone are insufficient)
Panic disorder
Obsessive compulsive disorder (OCD)
Examples of SSRI drugs?
Citalopram
Fluoxetine
Sertraline
Escitalopram
What is the mechanism of action for SSRIs?
Inhibits neuronal reuptake of serotonin (5-HT) from the synaptic cleft by blocking the serotonin transporter, hence increase in serotonin availability for binding to postsynaptic receptors.
This helps improve mood and physical symptoms in depression and relieve symptoms of panic and obsessive disorders.
What are the important adverse effects of SSRIs?
GI upset:
- changes in appetite
- changes in wt
Hypersensitivity reaction (skin rash)
Hyponatraemia (elderly pts may also present with confusion and reduced consciousness)
Suicidal thoughts and behaviour
May lower the seizure threshold
Prolong QT interval (arrhythmias)
Increase risk of bleeding
Serotonin syndrome (if high dose, overdose, or combined with other serotonergic drugs like antidepressants and tramadol)
Sudden withdrawal can lead to GI upset, neurological, influenza-like symptoms, and sleep disturbance.
Warnings of SSRIs?
Caution in pts with increased of adverse effects including those with:
- epilepsy
- peptic ulcer disease
Young people can only be prescribed by specialists due to:
- poor efficacy
- increased risk of self-harm and suicidal thoughts
Hepatic impairment -reduce dose.
Important interactions of SSRIs?
May lead to serotonin syndrome, do not combine with:
- MAOIs (monoamine oxidase inhibitors)
- serotonergic drugs (e.g. tramadol)
SSRI alongside aspirin or NSAIDs -consider gastroprotection due to risk of bleeding (PPI)
SSRI alongside anticoagulants increase bleeding risk.
Do not combine with drugs that prolong QT interval (e.g. antipsychotics).
How are SSRIs monitored?
Symptoms reviewed 1-2 wks after starting tx and regularly thereafter.
No effect at 4 wks, consider changing dose or drug.
If there is an effect at 4 wks, do not adjust dose until after 6-8 wks of therapy.
How would you explain to the pt about taking a SSRI drug?
SSRI medicines aim to increase certain chemicals (serotonin) in the brain to help improve symptoms over a few weeks, particularly sleep and appetite.
Must carry on the drug tx for at least 6 months after they feel better. This is to stop the depression from returning. (2 years for recurrent depression).
Warn pt to not stop tx suddenly as it can cause flu-like withdrawal symptoms and sleeplessness. When the time comes to stop tx, the dose will be reduced slowly over 4 wks. (fluoxetine has the lowest risk of withdrawal symptoms)
Discuss about referring them for psychological therapy, which may offer more long term benefits than drug treatment.
There are several side effects as with any medication, for e.g. changes in appetite, wt changes, diarrhoea, constipation, confusion, insomnia, suicidal thoughts and behaviour.
Which SSRIs are commonly prescribed?
Citalopram
Sertraline
Both these drugs have fewer drug interactions compared to other SSRIs.
What is serotonin syndrome?
It is a medical emergency that is caused by high levels of serotonin within the brain.
How do pts present in serotonin syndrome?
Pts present with a triad of symptoms:
- autonomic hyperactivity
- neuromuscular abnormality
- mental status changes
Autonomic hyperactivity:
- HTN
- tachycardia
- hyperthermia
- hyperactive bowel sounds
- excessive sweating
Neuromuscular abnormality
- tremor
- clonus
- hypertonicity
- hyperreflexia
Mental status change:
- anxiety
- agitation
- confusion
- coma
How is serotonin syndrome managed?
Stop the drug that is causing the symptoms (e.g. SSRI or SNRI)
Severe cases may require ICU.
Common indications of valproate?
Epilepsy (seizure prophylaxis)
Convulsive status epilepticus
Bipolar disorder (acute tx of manic episodes, prophylaxis against recurrence)
Important adverse effects of valproate?
GI upset:
- nausea
- GI irritation
- diarrhoea
Neurological and psychiatric effects:
- tremor
- ataxia
- behavioural disturbances
Thrombocytopenia
Transient increase in liver enzymes
Hypersensitivity reaction (e.g. hair loss)
Rare life threatening effects:
- liver injury
- pancreatitis
- bone marrow failure
- antiepileptic hypersensitivity syndrome
Warnings of valproate?
Avoid in:
- women of child-bearing age (particularly around conception, first trimester of pregnancy -can lead to fetal abnormalities)
- hepatic impairment
Renal impairment -reduce dose.
Fetal abnormalities include:
- neural tube defects
- craniofacial
- cardiac and limb abnormalities
- developmental delay
Important interactions of valproate?
Valproate inhibit hepatic enzymes, which increases plasma concentration and risk of toxicity with lamotrigine and drugs metabolised by cytochrome P450 enzymes (e.g. warfarin).
Increase risk of seizures due to CYP inducers.
Adverse effects are increased by CYP inhibitors.
Efficacy of antiepileptic drugs are reduced by drugs that lower the seizure threshold (e.g. antipsychotics, tramadol).
How is valproate monitored?
Monitor efficacy by comparing seizure frequency before and after starting tx.
Measure LFTs and prothrombin time before and during the first 6 months of tx.
Check plasma valproate concentration for adherence or toxicity.
How would you explain to the pt about taking a valproate drug?
Valproate medicines aim to reduce frequency of seizures or help improve symptoms in bipolar disorder.
Warn pt that they may experience indigestion or tummy upset when starting tx, but will settle in a few days. It can be reduced by taking the tablet with the food.
There are several side effects as with any medication, but if they experience lethargy, loss of appetite, vomiting or abdominal pain, bruising, fever, or mouth ulcers, then seek urgent medical advice.
Discuss risks for contraception and pregnancy in women.
Advise pts to not drive unless they have been seizure-free for 12 months and for 6 months after changing or stopping tx.
Common indications of lithium?
Biopolar disorder
Adverse effects of lithium?
Tremor
Nausea
Vomiting
Diarrhoea
Dry mouth
Feeling tired or sleepy
Visual disturbances
How is lithium monitored?
Routine serum-lithium monitoring should be performed weekly after initiation and after each dose change until concentrations are stable, then every 3 months for the first year, and every 6 months thereafter.
Patients who are 65 years and older, taking drugs that interact with lithium, at risk of impaired renal or thyroid function, raised calcium levels or other complications, have poor symptom control or poor adherence, or whose last serum-lithium concentration was 0.8 mmol/litre or higher, should be monitored every 3 months.
Additional serum-lithium measurements should be made if a patient develops significant intercurrent disease or if there is a significant change in a patient’s sodium or fluid intake.
