Nervous System Flashcards
Common indications of SSRIs?
1 - First line in Mild, Moderare-Severe Depression
2 - Panic Disorder
3 - Obsessive Compulsive Disorder
SSRI Mechanism of Action? and how do they differ from Tricyclic antidepressants?
SSRIs inhibit neuronal reuptake of serotonin, thereby increasing its availability for neurotransmission.
They differ from TCA’s because they do not inhibit noradrenaline reuptake. Their efficacy is similar but SSRIs have less side effects
Important adverse effects of SSRIs?
1 - GI upset, appetite and weight distubance. Endocrine effect.
2 - Hypersensitivity and Skin Rash.
- Lower Seizure Threshold!! Hyponatraemia which precipitating confusion, and reduced consciousness especially in elderly. Can also cause Serotonin syndrome: Autonomic Hyperactivity / Altered Mental State and NeuroMuscular Excitation. Neurological effect.
4 - Increased Risk of Bleeding and Prolonged QT interval. Cardiac effect
What does sudden withdrawal of SSRIs cause?
Flu Like withdrawal Symtoms:
Warnings with SSRIs?
Prescribe in caution in Epilepsy and Peptic ulcer Disease.
SSRIs are associated with suicidal thoughts and self harm.
Dose reduction needed in hepatic impairment as metabolised by the liver
Interactions with SSRIs
SSRIs should not be given with ►MAOIs as this can increase synaptic serotonin levels, causing Serotonin Syndrome.
GI protetction should be prescribed with patients taking SSRIs with aspirin or NSAIDs due to an increased risk of GI bleed.
Drugs that prolong QT interval e.g Antipsychotics
Examples of SSRIs
Citalopram (safest)
Fluoxetine
Sertraline
Escitalopram (safest)
Prescription advise on SSRIs
Starting dose is low and once daily. Dose increased according to response.
Communication to patients on Citalopram?
Communication to patients on Citalopram?
- Psycological therapy may offer more long term benefits
- Carry on with drug for at least 6 months after they feel better to stop the depression from coming back (2 years if the depression is recurrent)
- Do not stop taking this medicine suddenly: can cause Tummy upset, flu symtoms and weight loss + sleepyness
- Reduce the dose slowly over 4 weeks
Monitoring for SSRIs?
SSRI Symptoms to be reviewed over 1-2 weeks of starting. If no efect seen at 4 weeks, consider changing the dose o
Common indications of Tricyclic Antidepressants?
Common indications of Tricyclic Antidepressants?
- Second Line Tx to Moderate - Severe Depression
- Treatment of Neuropathic pain (unlicensed)
Mechanism of Action of TCAs?
Mechanism of Action of TCAs?
- Inhibit neuronal uptake of Serotonin and noradrenaline to improve mood and physical symptoms
- Blockade of a wide range of receptors: H1/ σ1 /σ2 / D2
Improtant Adverse effects of TCAs?
Improtant Adverse effects of TCAs?
- Blockade of Antimuscarininc receptors – BCUD: Blurry Vision/ Consitpation/ Urinary Retention/ Dry Mouth. Antimuscarinic effects
- Blockade of Histamine Receptors and Alpha: Sedation and Hypotension
- May Cause Arrhythmias and Prolong QT Interval. Cardiac Effects
- Centrally, may cause convulsions, hallucinations and mania. Central Effects
- Blockade of Dopamine receptors can cause breast changes and sexual dysfunction
- Rarely may cause EPSEs (tremor and dyskinesia)
Any sudden withdrawal can cause flu-like symtoms and GI upset. An overdose can be fatal causing respiratory failure. Respiratory effects
Warnings associated with TCAs?
Warnings associated with TCAs?
- Elderly people with Cardiovascular disease
- Epileptic people
- Constipated individuals / Prostatic Hypertrophy / Raised intra-ocular pressure is all made worse by antimuscarinic effects
Important interactions of TCAs?
Important interactions of TCAs?
- Avoid any class of SSRI
- Avoid MAOIs
- Avoid use with other drugs that cause Antimuscarinic / Sedative / Hypotensive effects of other drugs
Example of TCAs?
Amitriptyline
Lofepramine
Prescription advice in neuropathic pain for Amitriptyline?
Prescription advice in neuropathic pain for Amitriptyline?
Start at Lower dose e.g 10mg at night.
What doe you communicate to the patient on TCA?
What doe you communicate to the patient on TCA?
- Takes a few weeks to reach maximum effect
- Psycological therapy may be better in long term
- Carry on for at least 6 months when feeling better (2 years if its recurrent depression)
- Do not stop suddenly, may cause withdrawal symptoms and sleeplessness, rather, reduce over a 4-week period when time comes to stop treatment
- Discuss side effects at an early stage to encourage them to take it.
Indication for Venlaflaxine and Mirtazapine?
Indication for Venlaflaxine and Mirtazapine?
- Major depression
- Venlaflaxine only for Generalised Anxiety Disorder
Mechanism of Action of Venla and Mirt
Mechanism of Action of Venla and Mirt
Venlafaxine is and Serotonin and Noradrenaline Reuptake inhibitor (SNRI)
Mirtazapine is an antagonist of inhibitory pre-synampic σ2 - adrenoceptors.
Both drugs increase the availability of Monoamines for neurotransmission.
Important adverse effect of Venlafaxine and Mirtazapine?
Important adverse effect of Venlafaxine and Mirtazapine?
- GI Upset ( Dry mouth / Nausea /Change in weight and Diarrhoea or Constipation)
- CNS Effects (Headache / Abnormal Dreams / insomnia / Confusions / Convulsion).
- Serotonin Syndrome
- Venlafaxine Prolongs QT + Increases risk of Ventricular Arrhythmias
- Sudden Withdrawal causes GI upset and Flu Symtoms, and Sleeplesness
Presscription advice on Venlafaxine and Mirtazapine?
General Starting doses are 37.5mg BD for Venlafaxine.
General Starting doses are 15mg OD for Mirazapine, take at ngiht to benefit from its sedative effects
What do we communcate to patients on Venla or Mirt?
What do we communcate to patients on Venla or Mirt?
- Improves symtoms over a few weeks.
- Psycological therapy has long term benefits than drug treatment
- carry on for at least 6 months after you feel better to stop depression from coming back (or 2 years if recurrent)
- Do not stop suddenly
If on Mirtazapine: Watch out for Sore throat or symptoms of infection
Indication and Treatment for Metoclopramide and Domperidone?
Prophylaxis and Treatment of Nausea and Vomiting in a wide array of condiions.
MOA of Metoclopramide and Domperidone?
MOA of Metoclopramide and Domperidone?
Theyre D2 - Receptor Antagonists. D2 receptors are the main receptors in the CTZ which are responsible for sensing emeotgenic (make u sick) substances in the blood. Dopamine is a gut neurotransmitter that promotoes relaxation of stomach. Drugs that block D2 - receptors have a prokinetic effect promoting gastric emptying.
Important side effects of D2 - Receptor antagonists?
Important side effects of D2 - Receptor antagonists?
Diarrhoea main side effect
Metoclopramide can induce EPSE movement abnormalities. If treatment is short term it appears as acute dystonic movement.
domperidone does not cross the blood brain barrier so does not cause this.
Warnings of D2 receptor antagonists?
Side effects of D2 receptor antagonists?
EPSE are more common in children and young adults
Contrindicated in patients with GI obstruction due to its prokinetic effects.
Important interactions of D2 Antipsychotics
D2 Antagonist + TCA Antipsycotics has increased chance of EPSEs
Can Antagonise effects of Parkinsons disease treatments. But Domperidone is ok!
Domperidone is contra-indicated for use in conditions where cardiac conduction is, or could be impaired, or where there is underlying cardiac disease, when administered concomitantly with drugs that prolong the QT interval or potent CYP3A4 inhibitors, and in severe hepatic impairment;
Both Metoclopramdie and Domperidone prolong QT
What to communicate to a patient taking Metoclopramide or Domperidone?
What to communicate to a patient taking Metoclopramide or Domperidone?
- This is anti-sickness medication
- Watch our for muscle spasms and any abnromal movements
- Both drugs are intended for short term use.(MHRA warning)
Indications for Antiemetics ? (H1) receptor
Motion Sickness or Vertigo (whirling), particularly in the context of motion sickness.
Mode of Action of Histamine antags?
Mode of Action of Histamine antags?
The various pathways linked to Gut irritation / Nausea and Vomiting / drugs all converge on a vomiting centre in the medulla which recieved inputs from the Chemoreceptor triggoring zone. Drugs such as Cyclizine block its communication
Important adverse effects of H1 receptor antagonists?
Drowsiness. Cyclizine is the least sedating drug in this class.
Due to anticolinergic effects –DCUB– Can cause dry throat and mouth.
Warnings with H1 antagonists?
Due to sedating effect avoid in hepatic encephalopathy.
Avoid in patients susptible to anticholinergic effects who may develop urinary retention e.g those with prostatic hypertrophy.
Important interactions of H1 receptor antags and communication?
Sedation may be greater when combined with other sedative drugs such as Benzodiazepines and opioids and Mirtazapine.
Anticolinergic effects may be more pronounced in patients on Antimuscarinics e.g Ipratropium or Tiotropium
Tell patient its anti-sickness and may cause drowsiness and impair ability to perform tasks such as driving.
Common indications for Phenothiazines?
Common indications for Phenothiazines?
- Prophylaxis of nausea and vomiting and vertigo. (but due to their side effect profile other antiemetics are preferred
- Psychotic disorders, such as schizophrenia, where they are used as first generation typical antipsychotics
Important adverse effects of Phenothiazines?
Important adverse effects of Phenothiazines?
- Drowsiness and Postural Hypotension
- EPSEs arising from D2 blockade – in the form of acute dystonic movements and tardive dyskinesia.
- QT prolongation, just like all antipsychotics
Warnings associated with Phenothiazine antiemetics?
Warnings associated with Phenothiazine antiemetics?
- Their sedative effects
- Potential hepatotoxicity so avoid in liver disease.
- Avoid in those with potential BPH due to antimuscarinic effects
- Reduce dose in elderly
Interactions associated with Phenothiazine antiemetics
Interactions associated with Phenothiazine antiemetics
- Drugs that prolong the QT Interval: CAMAS > Ciprofloxacin / Amiodarone / Macrolides / Antipsychotics / SSRIs
What to communicate to patients on Phenothiazines
What to communicate to patients on Phenothiazines
- It’s Antisickness medication
- Drowsy Side effects when driving might be dizziness on standing.
- Seek medical advice when there is any muscle spasms
Examples of Phenothiazines?
Examples of Phenothiazines?
- Prochlorperazine
- Chlorpromazine
Common indications of 5-HT3 receptor antagonists?
Common indications of 5-HT3 receptor antagonists?
- Nausea and Vomiting generally in the context of chemotherapy
Mechanism of action of 5-HT3 receptor antagonists? And examples?
Mechanism of action of 5-HT3 receptor antagonists? And examples?
- Ondansetron
- Granisetron
5-HT3 receptors are located in the CTZ are responsible for sensing emetogenic substances in the blood. Serotonin is the key neurotransmitter released by the gut in response to emetogenic stimuli. Blocking 5-HT3 receptors, means that you stop transmission to the vomiting centre in the brain caused by emetogenic stimuli (like drugs) in the blood. It also means that you block visceral stimuli (gut infection and radiotherapy) but not in motion sickness, as there’s no emetogenic substance here.
Important Adverse Effects with 5-HT3 receptor antagonists?
side effects? Its rare with this medication, although constipation/ diarrhoea and headaches can occur.
Important interactions with 5-HT3 receptor antagonists?
Important interactions with 5-HT3 receptor antagonists?
- Drugs that prolong the QT interval such as CAMAS and Quinine…
Common Indications of Antihistamines?
Common Indications of Antihistamines?
1 – First line for Allergies and Hay Fever (Seasonal Rhinitis)
2 – To aid Itchiness (Pruritus) and hives (Urticaria) attach image
3 – Adjunct to Anaphylaxis
4 – Other drugs in H1 class used for Nausea and Vomiting.
Important adverse effects of Antihistamines?
Important adverse effects of Antihistamines?
1 Sedation (caused by first generation Antihistamines)
2 Newer, second generation Antihistamines do not have this effect as they don’t cross BBB (Cetirizine / Loratadine / Fexofenadine)
Warnings with antihistamines?
Warnings with antihistamines?
- Sedating antihistamines are to be avoided in Liver disease as this may exacerbate hepatic encephalopathy
Interactions of OTC antihistamines?
No major OTC interactions, but avoid chlorphenamine and alcohol as may increase the sedative effect
Common indications of First Generation Antipsycotics and examples?
Common indications of First Generation Antipsycotics and examples?
- Haloperidol
- Chlorpromazine
- Prochlorperazine
- used in Urgent Treatment of Psychomotor agitation that is causing dangerous or violent behaviour
- Schizophrenia, particularly when the metabolic side effects of second-generation antipsychotics are problematic. This treats the positive symptoms.
- Bipolar Disorder in acute phases
- Nausea and Vomiting particularly in palliative care settings
Mechanism of action of First Generation Antipsycotics?
Mechanism of action of First Generation Antipsycotics?
- Antipsychotics block post-synaptic dopamine D2 receptors
- D2 receptors located in Mesolimbic/Mesocortical pathway + Nigrostriatal Pathway + Tubero-hypophyseal pathway + CTZ (where it blocks nausea and vomiting)
Important adverse effects of First Generation Antipsycotics?
Important adverse effects of First Generation Antipsycotics?
- Blocking Nigrostriatal pathway = EPSEs
- Drowsiness / Hypotension and QT Prolongation
- Blocking Tubero-hypophyseal pathway causes erectile dysfunction and hyperprolactinaemia.
What are the characteristics of EPSEs?
What are the characteristics of EPSEs?
These symptoms include: DART B “DARBY”
- Dystonia (continuous spasms and muscle contractions)
- Akathisia (inner restlessness)
- PaRkinsonism (characteristic symptoms such as rigidity and Tremor),
- Tardive dyskinesia (irregular, jerky movements like lip smacking) develops months/ years after stopping therapy.
- Bradykinesia (slowness of movement),
Important interactions of First Generation Antipsychotics?
Important interactions of First Generation Antipsychotics?
- Increases risk of Stroke in Dementia
- Caution in elderly!
- Avoid this in Parkinsons man..
Imprtant ineractions First Generation Antipsycotics?
Imprtant ineractions First Generation Antipsycotics?
- Drugs prolonging QT. e.g Amiodarone and Macrolides
Common indications of Second-Generation Atypical Antipsychotics
Common indications of Second-Generation Atypical Antipsychotics
- Urgent treatment of Severe Psychomotor Agitation leading to dangerous or violent behaviour, or to calm such patients to permit assessment
- Negative symptoms of Schizophrenia
- When EPSEs have complicated the use of first-generation (typical) antipsychotic
- Bipolar disorder, particularly in acute episodes or mania or hypomania
MOA of Second-Generation Atypical Antipsychotics
MOA of Second-Generation Atypical Antipsychotics
- Blockade of Post-Synaptic Dopamine D2 receptors (Nigro/Tubero/Meso)
- Higher Affinity for other receptors (Particularly 5HT-2a receptors), and a characteristic of ‘looser binding’ to the D2 receptors (particularly clozapine and quetiapine). This may account for its lower risk of EPSEs.
Important Adverse Effects of Second-Generation Atypical Antipsychotics:
Important Adverse Effects of Second-Generation Atypical Antipsychotics:
- Sedation
- Blocking dopamine in the nigrostriatal pathway may cause EPSEs. “DARTB” “DARBY”
- Metabolic disturbances: Weight Gain / Diabetes Mellitus / Lipid changes.
- Antipsychotics can prolong QT intervals + Cause Arrhythmias
- Risperidone blocks D2 in Tubero, causing secretion of prolactin and breasts may develop.
- Clozapine causes a severe deficiency of neutrophils (agranulocytosis) and SLE
Warnings Associated with Second-Generation Atypical Antipsychotics
Warnings Associated with Second-Generation Atypical Antipsychotics
- Avoid in cardiovascular disease, myocarditis etc
- Severe heart disease or history of neutropenia
Important interactions associated with Second-Generation Atypical Antipsychotics
Important interactions associated with Second-Generation Atypical Antipsychotics
- Drugs that increase Sedation
- QT Prolonging drugs
Administration details regarding Clozapine:
Administration details regarding Clozapine:
- Fasting blood glucose should be measured at baseline, at 4–6 months, and then yearly. Patients taking clozapine should have fasting blood glucose tested at baseline, after one months’ treatment, then every 4–6 months.
- Blood lipids and weight should be measured at baseline, at 3 months (weight should be measured at frequent intervals during the first 3 months), and then yearly with antipsychotics. Patients taking clozapine require more frequent monitoring of these parameters: every 3 months for the first year, then yearly.
- Monitor leucocyte and differential blood counts. Clozapine requires differential white blood cell monitoring weekly for 18 weeks, then fortnightly for up to one year, and then monthly as part of the clozapine patient monitoring service.
Communication for Second-Generation Atypical Antipsychotics
Communication for Second-Generation Atypical Antipsychotics
- Make HCPs aware of your Treatment.
- Report any infective symptoms
Monitoring for Second-Generation Atypical Antipsychotics
Monitoring for Second-Generation Atypical Antipsychotics
- FBC / Renal and Liver
