Agitation, psychomotor Flashcards
(26 cards)
1
Q
(Antiemetics) Phenothiazines- prochlorperazine, chlorpromazine
Common indications
A
- Prophylaxis and treatment of nausea and vomiting in a wide range of conditions, particularly when due to vertigo. However, due to their side effect profile, other antiemetic classes are usually preferable
- Psychotic disorders, such as schizophrenia, where they are used as first-generation (typical) antipsychotics
2
Q
(Antiemetics) Phenothiazines- prochlorperazine, chlorpromazine
MOA
A
- N&V is triggered by a variety of factors, including gut irritation, drugs, motion and vestibular disorders, as well as higher stimuli (sight, smells, emotions)
- The various pathways converge on a ‘vomiting centre’ in the medulla, which recieves inputs from the CTZ, the solitary tract nucleus (which is innervated by the vagus nerve), the vestibular system and higher neurological centres
- The antiemetic properties of phenothiazines arise from blockade of various receptors, including dopamine (D2) receptors in the CTZ and gut and, to a lesser extent, histamine (H1) and acetylcholine receptors in the vomiting centre and vestibular system
- This makes them effective for N&V in a wide range of situations, including chemotherapy, radiotherapy and vertigo
3
Q
(Antiemetics) Phenothiazines- prochlorperazine, chlorpromazine
Important adverse effects
A
- Drowsiness and postural hypotension are relatively common with phenothiazines
- Movement abnormalities, termed extrapyramidal syndromes, are a major drawback of their use
- They arise from D2 receptors blockade via the same mechanism as for other first-generation (typical) antipsychotics
- In the context of short-term treatment for N&V, this is most likely to take the form of an acute dsytonic reaction such as oculogyric crisis
- In longer-term treatment (which is more likely when they are used as an antipsychotic), other extrapyramidal syndromes such as tardive dyskinesia may occur
- Like all antipsychotics, phenothiazines can cause QT-interval prolongation
4
Q
(Antiemetics) Phenothiazines- prochlorperazine, chlorpromazine
Warnings
A
- Due to their sedative effect and potential for hepatotoxicity, these drugs should be avoided in patients with severe liver disease
- They should also be avoided in patients susceptible to anticholinergic side effects, such as those with prostatic hypertrophy (who may develop urinary retention)
- Doses should be reduced in the elderly
5
Q
(Antiemetics) Phenothiazines- prochlorperazine, chlorpromazine
Important interaction
A
- You should consult the BNF when prescribing for a patient taking these drugs as there is an extensive list of interactions
- Prominent among these are drugs that prolong the QT interval, such as antipsychotics, amiodarone, ciprofloxacin, macrolides, quinine and SSRIs
6
Q
(Antiemetics) Phenothiazines- prochlorperazine, chlorpromazine
Prescription
A
- We would suggest you seek senior or specialist advice when contemplating the prescription of a phenothiazine, as other drugs should usually be tried first
- A typical prescription in the context of N&V might be for prochlorperazine 20mg OD or 12.5mg IM to settle the acute attack, with further oral doses (e.g. 10mg 12-hrly) prescribed if necessary for ongoing symptoms
*
7
Q
(Antiemetics) Phenothiazines- prochlorperazine, chlorpromazine
Administration
A
- Intramuscular prochlorperazine should be administered by deep injection in a large muscle
8
Q
(Antiemetics) Phenothiazines- prochlorperazine, chlorpromazine
Communication
A
- Explain that you are offering an anti-sickness medicine
- Although it is generally effective, it does not work for everyone and a second or different medicine may be necessary
- Ask them to let you know if they do not achieve satisfactory relief
- Discuss the potential for drowsiness (and its implications for driving) and dizziness and standing
- Ask them to stop taking the medicine and seek medical advice if they develop any muscle spasms or movement abnormalities
9
Q
(Antiemetics) Phenothiazines- prochlorperazine, chlorpromazine
Monitoring
A
- Resolution of symptoms is the best guide to efficacy, in prolonged use you should monitor the patient for extrapyramidal features, as these may be subtle (e.g. an increased tendency to falls) and their relationship to the drug may not be obvious to patients or other HCP
10
Q
Antipsychotic (first-generation- typical) HALOPERIDOL, CHLORPROMAZINE, PROCHLORPERAZINE
common indications
A
- Urgent treatment of severe psychomotor agitation that is causing dangerous or violent behaviour, or calming patients to permit assessment
- Schizophrenia, particularly when the metabolic side effects of second-generation (atypical) antipsychotics are likely to be problematic
- Bipolar disorder, particularly in acute episodes of mania or hypomania
- Nausea and vomiting, particularly in the palliative care setting
11
Q
Antipsychotic (first-generation- typical) HALOPERIDOL, CHLORPROMAZINE, PROCHLORPERAZINE
MOA
A
- Antipsychotic drugs block post-synaptic dopamine D2-receptors.
- There are three main dopaminergic pathways in the central nervous system
- The mesolimbic/mesocortical pathway runs between the midbrain and the limbic system/frontal cortex
- D2 blockade in this pathway is probably the main determinant of antipsychotic effect, but this is incompletely understood
- The nigrostriatal pathway connects the substantia nigra with the corpus striatum of the basal ganglia
- The tuberohypophyseal pathway connects the hypothalamus with the pituitary gland
- D2 receptors are also found in the CTZ, where blockade accounts for their use in N&V
- All antipsychotics, but particularly chlorpromazine, have some sedative effect
- This may be beneficial in the context of acute psychomotor agitation
12
Q
Antipsychotic (first-generation- typical) HALOPERIDOL, CHLORPROMAZINE, PROCHLORPERAZINE
Important adverse effects
A
- Extrapyr.amidal effects- movement abnormalities that arise from D2 blockade in the nigrostriatal pathway- are the main drawback of first-generation antipsychotics
- They take several forms: acute dystonic reactions are involuntary parkinsonian movements or muscle spasm; akathisia is a state of inner restlessnes, andd the neuroleptic malignant syndrome is rare but life-threatening side effect characterised by rigidity, confusion, autonomic dysregulation and pyrexia
- These all tend to occur early in treatment, by contrast, tardive dyskinesia is a late adverse effect (tardive, late), occurring after months or years of therapy
- This comprises movements that are pointless, involuntary and repetitive (e.g. lip smacking)
- It is disabling and may not resolve on stopping treatment. Other adverse effects include Drowsiness, hypotension, QT-interval prolongation, ED and hyperprolactinaemia due to tuberophypophyseal D2-blockade
- (e.g. mentrual disturbance, galactorrhoea and breast pain)
13
Q
Antipsychotic (first-generation- typical) HALOPERIDOL, CHLORPROMAZINE, PROCHLORPERAZINE
Warnings
A
- Elderly patients are particularly sensitive to antipsychotics, so start with lower doses. Antipsychotics should ideally be avoided in dementia, as they may increase the risk of death and stroke
- They should be avoided if possible in Parkinson’s disease due to their extrapyramidal effects
14
Q
Antipsychotic (first-generation- typical) HALOPERIDOL, CHLORPROMAZINE, PROCHLORPERAZINE
Important interactions
A
- Consultant the BNF when prescribing for a patient taking antipsychotics as there is an extensive list of interactions
- Prominent among these are drugs that prolong the QT interval (e.g. amiodarone, macrolides)
15
Q
Antipsychotic (first-generation- typical) HALOPERIDOL, CHLORPROMAZINE, PROCHLORPERAZINE
Prescription
A
- Regular treatment is required to treat schizophrenia and should only be started or adjusted under the guidance of a psychiatrist
- A single dose may be used to control acute or violent behaviour
- A common choice is haloperidol 0.5-3.0mg IM, although higher doses may be used in extreme cases
- This should be given only under the guidance of an appropriately experienced clinicians
- For the control of nausea, haloperidol is used in regular small oral or SC doses (e.g. 1.5mg at night) or as a component of a continuous SC infusion
16
Q
Antipsychotic (first-generation- typical) HALOPERIDOL, CHLORPROMAZINE, PROCHLORPERAZINE
Administration
A
- For regular administration, typical antipsychotics can be taken orally (tablet and liquid) or given by slow-release IM (depot) injection
- In emergenecies, haloperidol is usually given by rapid-acting IM injection and occasionally IV for rapid control of symptoms, although it is not licensed by this route.
- Intravenous haloperidol should be only administered by clinicians capable of managing neurological and cardiovascular side effects including arrhthmias such as torsades de pointes (a form of ventricular tachycardia), which are more likely when antipscyhotics are given by injection or in high dose
17
Q
Antipsychotic (first-generation- typical) HALOPERIDOL, CHLORPROMAZINE, PROCHLORPERAZINE
Communication
A
- Adherence is a significant issue when treating psychiatric disorders, both because of the underlying disease and adverse effects of treatment
- Good communication with your patient about the aims and benefits of treatments, as well as its potential side effects, are therefore very important.
- It is also important to emphasise that patients should report that they are taking antipsychotics to other HCP involved in their care, as many other medicines can interfere with the way they work
18
Q
Antipsychotic (first-generation- typical) HALOPERIDOL, CHLORPROMAZINE, PROCHLORPERAZINE
Monitoring
A
- The aim of treatment with antipsychotics is control of symptoms, so frequent reviews of symptoms and signs are important
- The antipsychotics effects may take several weeks to become establised and the dose may need to be adjusted to obtain the optimum balance between beneficial and adverse effects
- When using high doses for acute control of psychotic/violent behaviour the dose-response relationship is unpredictable, so you should ensure that appropriate monitoring is available to detect neurological, respiratory and CV depression
19
Q
Antipsychotic (Second-generation atypical) QUETIAPINE, OLANZAPINE, RISPERIDONE, CLOZAPINE
Common indications
A
- Urgent treatment of severe psychomotor agitation leading to dangerous or violent behaviour, or to calm such patients to permit assessment
- Schizophrenia particularly when extrapyramidal side effects have complicated the use of first-generation (typical) antipsychotics or when negative symptoms are prominent
- Bipolar disorder, particularly in acute episodes of mania or hypomania
20
Q
Antipsychotic (Second-generation atypical) QUETIAPINE, OLANZAPINE, RISPERIDONE, CLOZAPINE
MOA
A
- Antipsychotic drugs block post-synaptic dopamine D2-receptors
- There are three main dopaminergic pathways in the central nervous system
- The mesolimbic/mesocortical pathway runs between the midbrain and the limbic system/frontal cortex
- D2 blockade in this pathway is probably the main determinant of antipsychotic effect, but this is incompletely understood
- The nigrostriatal pathway connects the substantia nigra with the corpus striatum of the basal ganglia
- The tuberohypophyseal pathway connects the hypothalamus with the pituitary gland
- Features that distinguish second-generation antipsychotics from first-generation agents are improved efficacy in treatment-resistant schizophrenia (particularly clozapine) and against negative symptoms and a lower risk of extrapyramidal symptoms
- Possible mechanisms for these differences include a higher affinity for other receptors (particularly 5-HT2A receptors) and a characteristic of looser binding to the D2-receptors (in the case of clozapine and quetiapine)
21
Q
Antipsychotic (Second-generation atypical) QUETIAPINE, OLANZAPINE, RISPERIDONE, CLOZAPINE
Important adverse effects
A
- Most antipsychotics cause some degree of sedation
- Blocking dopamine in the nigrostriatal pathway may produce movement abnormalities called extrapyramidal effects. These are more common with First-generation antipsychotics, where they are discussed more fully
- Metabolic disturbance, including weight gain, diabetes mellitus and lipid changes, is a common problem with second-generation antipsychotics
- Antipsychotics can prolong the QT-interval and thus arrhythmias
- Risperidone has particular effects on dopaminergic transmission in the tuberohypophyseal pathway, which regulates prolactin
- This can cause breast symptoms (in both women and men) and sexual dysfunction
- Clozapine causes a severe deficiency of neutrophils (Agranulocytosis) in about 1% of patients, and rarely cause myocarditis
22
Q
Antipsychotic (Second-generation atypical) QUETIAPINE, OLANZAPINE, RISPERIDONE, CLOZAPINE
Warnings
A
- Antipsychotics should be used with caution in patients with cardiovascular disease
- Clozapine must be used in patients with severe heart disease or a history of neutropenia
23
Q
Antipsychotic (Second-generation atypical) QUETIAPINE, OLANZAPINE, RISPERIDONE, CLOZAPINE
Important interactions
A
- Sedation may be more pronounced when used with other sedating drugs
- They should not be combined with other dopamine-blocking antiemetics and drugs that prolong the QT interval (e.g. amiodarone, quinine, macrolides, SSRIs
24
Q
Antipsychotic (Second-generation atypical) QUETIAPINE, OLANZAPINE, RISPERIDONE, CLOZAPINE
Prescription
A
- Decisions to start treatment with a second-generation antipsychotic drug should be taken by a specialist
- They may be used both for treatment of acute symptoms and for prevention of subsequent attacks
- Options include daily oral treatment or intermittent slow-release IM (depot) injections
- Clozapine is considered when other agents have proved ineffective or intolerable
- You are most likely to encounter these drugs in patients already established on treatment, for example when they are admitted to hospital
- In this situation, you should not usually stop them, but must check carefully that the acute illness is not caused by the antipsychotics, that it does not present a contraindication to antipsychotic treatment, and that any new drugs introduced do not interact with the antipsychotic
25
Antipsychotic (Second-generation atypical) QUETIAPINE, OLANZAPINE, RISPERIDONE, CLOZAPINE
Communication
* When you encounter patients established on antipsychotic treatment, it is worth reminding them that they should always inform any HCP involved in their care what treatment they are on
* This is particularly important for antipsychotics as many other medicines can interfere with the way they work
* Patients taking clozapine should know about the need for regular blood test monitoring and of the need to report infective symptoms immediately
26
Antipsychotic (Second-generation atypical) QUETIAPINE, OLANZAPINE, RISPERIDONE, CLOZAPINE
Monitoring
* Assessment of symptoms and signs is the best form of monitoring for treatment efficacy
* For most antipsychotics, blood tests (typically full blood count, renal and liver profiles) are required at the start of treatment and periodically thereafter; an intensive monitoring programme is required for clozapine due to the risk of agranulocytosis
* Monitoring for metabolic and cardiovascular side effects is important for second-generation antipsychotics
* This includes measurement of weight, lipid profile and fasting blood glucose at baseline and intermittently during treatment
