QuestionSBA
QuestionChoice
Risperidone is associated with hypotension (usually dose-related) as opposed to hypertension
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Increased risk of hypertension
QuestionChoice
Risperidone has a lower risk of producing extrapyramidal side effects than typical antipsychotics such as chlorpromazine and haloperidol; however, there is still a risk of drug-induced Parkinsonism, particularly at higher doses. It does not, however, cause Parkinson's Disease
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Increased risk of Parkinson's Disease
QuestionChoice
Antipsychotic medications can cause weight gain and a rise in blood sugar; therefore are associated with an increased risk of developing diabetes, though this is less likely to be relevant in this case as it is a long-term effect
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Increased risk of hypoglycaemia
QuestionChoice
There is a small increased risk of stroke when starting certain antipsychotic medications. The National Institute for Health and Care Excellence (NICE) quotes an absolute risk increase of 1.22% (an extra 12 strokes per 1000 people starting an antipsychotic)
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Increased risk of stroke
QuestionChoice
Patients started on risperidone should be monitored for prolactin concentration at the start of therapy, at six months, and then yearly. Clozapine can cause agranulocytosis and therefore requires differential white blood cell monitoring weekly for 18 weeks, then fortnightly for up to one year, and then monthly. This is not the case for risperidone
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Increased risk of agranulocytosis
QuestionComment
Damn got me on the wording, gotta remember PD =/= Parkinsonism
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# Summary



# Typical antipsychotics

- Also known as 'first-generation' antipsychotics, these not only act as antagonists to D2 receptors but also on cholinergic, adrenergic and histaminergic receptors. The most commonly used medication in this class is **Haloperidol**, though other examples include Chlorpromazine and flupentixol. 
- Side effects can therefore be grouped according to receptor blockade (see below).

### Dopamine D2 Receptor Blockade:

1. **Extrapyramidal Symptoms (EPS):**
   - **Acute Dystonia:** Involuntary muscle contractions causing spasms.
   - **Akathisia:** Restlessness and an inability to sit still.
   - **Parkinsonism:** Tremors, rigidity, and bradykinesia (slowed movements).
   - **Tardive Dyskinesia:** Involuntary, repetitive movements, especially of the face.

2. **Hyperprolactinemia:**
   - Elevated levels of prolactin, leading to:
     - Menstrual irregularities in women.
     - Gynecomastia (breast enlargement) in men.
     - Sexual dysfunction in both genders.

### Other Receptors:

1. **Histamine H1 Receptor Blockade:**
   - **Sedation:** Drowsiness and sleepiness.

2. **Alpha-1 Adrenergic Receptor Blockade:**
   - **Orthostatic Hypotension:** A sudden drop in blood pressure upon standing, leading to dizziness or fainting.

3. **Muscarinic Receptor Blockade:**
   - **Anticholinergic Effects:**
     - Dry mouth.
     - Constipation.
     - Blurred vision.
     - Urinary retention.


# Atypical antipsychotics

- Also known as 'second-generation' antipsychotics, these are D2, D3 and 5-HT2A antagonists, with less overspill into other receptors. 
- As effective as typical antipsychotics (even slightly better at negative symptoms), and have a more favourable side effect profile with reduced extrapyramidal effects, but increased metabolic side-effects. 
- They are 1st line for new-onset psychosis. Examples include risperidone, quetiapine, olanzapine, aripiprazole and clozapine (see below). 

### Dopamine Receptor Blockade:

1. **D2 Receptor Blockade:**
   - **EPS (Extrapyramidal Symptoms):**
     - Atypicals generally have a lower risk of causing EPS compared to typicals.
     - Lower risk of tardive dyskinesia.

### Serotonin Receptor Blockade:

1. **5-HT2A Receptor Blockade:**
   - **Lower Risk of EPS:** Atypicals have a reduced risk of causing EPS due to serotonin receptor blockade.

### Other Receptors:

1. **Histamine H1 Receptor Blockade:**
   - **Sedation:** Although less common than with typicals, some atypicals can cause drowsiness.

2. **Alpha-1 Adrenergic Receptor Blockade:**
   - **Orthostatic Hypotension:** Some atypicals may cause a drop in blood pressure upon standing.

3. **Muscarinic Receptor Blockade:**
   - **Anticholinergic Effects:**
     - Generally less pronounced compared to typicals.
     - Mild dry mouth, constipation, or blurred vision.

### Metabolic Effects:

1. **Weight Gain:**
   - **Common Side Effect:** Atypical antipsychotics, in general, have a higher risk of causing weight gain compared to typicals.
   - **Varying Degrees:** The degree of weight gain can vary among different atypicals.

2. **Dyslipidemia and Glucose Metabolism:**
   - **Increased Risk:** Some atypicals are associated with an increased risk of dyslipidemia and impaired glucose metabolism.

3. **Prolactin Elevation:**
   - **Variable:** Some atypicals may elevate prolactin levels, leading to menstrual irregularities and sexual dysfunction.

### Other side effects:

1. **Seizures:**
   - **Low Risk:** Generally, atypicals have a lower risk of lowering the seizure threshold compared to typicals.

2. **QT Prolongation:**
   - **Potential Risk:** Some atypicals may have a mild effect on the QT interval, but the clinical significance varies.

3. **Increased risk of VTE and stroke in elderly**

### Monitoring

* Weight should be measured at the start of therapy, then weekly for the first 6 weeks, then at 12 weeks, at 1 year, and then yearly.
* Fasting blood glucose, HbA1c, and blood lipid concentrations should be measured at baseline, at 12 weeks, at 1 year, and then yearly. 
* Prolactin concentrations should also be measured at baseline.
* Before initiating antipsychotic drugs, an ECG may be required, particularly if there are cardiovascular risk factors (e.g. high blood pressure), if there is a personal history of cardiovascular disease, or if the patient is being admitted as an inpatient.
* Blood pressure monitoring before starting therapy, at 12 weeks, at 1 year and then yearly during treatment and dose titration of antipsychotic drugs.

# Clozapine

- Clozapine is an atypical antipsychotic that is indicated if there is failure of treatment of 2 other antipsychotic medication, known as treatment-resistant schizophrenia.
- Treats both positive and negative symptoms, slightly more effective than other antipsychotics.
- Important side effects include: **agranulocytosis**, neutropenia, reduced seizure threshold, myocarditis, slurred speech (due to hypersalivation), constipation (most common cause of mortality when related to clozapine use).

### Monitoring

- Due to its unique and potentially serious side effect profile, monitoring while on clozapine is very important.
- Patients should have weekly FBC (to look at white cell counts) for the first 18 weeks of treatment then fortnightly for up to one year, and then monthly.
- Blood lipids and weight should be measured at baseline, every 3 months for the first year, and then yearly.
- Fasting blood glucose should be tested at baseline, after one months’ treatment, then every 4–6 months.


# Neuroleptic Malignant Syndrome

Neuroleptic Malignant Syndrome (NMS) is a rare, but potentially life-threatening, idiosyncratic reaction to antipsychotic medications, particularly those that block dopamine receptors. It typically occurs as a response to the introduction or an increase in the dosage of neuroleptic medications.

### Clinical Features

1. **Hyperthermia:**
   - Profound elevation of body temperature is a hallmark feature.
   
2. **Altered Mental Status:**
   - Fluctuating levels of consciousness, ranging from confusion to catatonia.

3. **Autonomic Dysregulation:**
   - Dysautonomia characterized by fluctuations in blood pressure, tachycardia, and diaphoresis.

4. **Rigidity:**
   - Generalized muscle stiffness, often described as "lead-pipe" rigidity.

### Differential Diagnosis

- **Malignant Hyperthermia** - a rare, genetic condition triggered by certain medications, often during anaesthesia.

- **Serotonin Syndrome** similar to NMS but associated with serotoninergic medications. Presents with hyperthermia, autonomic dysregulation, and altered mental status.

### Investigations 

- Bloods:
	- FBC - Monitoring for potential leukocytosis or signs of infection.
   - **Creatine Kinase (CK) Levels:**  Markedly elevated CK levels are often observed due to muscle breakdown.
   - Renal and Liver Function Tests: monitoring organ function due to the potential systemic effects.
   
### Management

1. **Discontinuation of Causative Agent:**
   - Immediate cessation of the implicated neuroleptic medication.

2. **Supportive Care:**
   - Aggressive cooling measures to address hyperthermia, including cooling blankets and IV fluids to prevent renal failure.

3. **Benzodiazepines:**
   - Administering benzodiazepines to manage agitation and muscle rigidity.

4. **Dantrolene:**
   - Consideration of dantrolene, a skeletal muscle relaxant, in severe cases.

5. **Intensive Monitoring:**
   - Continuous monitoring of vital signs, fluid balance, and laboratory parameters.
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Risperidone use in elderly patients with dementia is associated with a small increased risk of stroke.
A 76-year-old female is diagnosed with Alzheimer's dementia. Over the last few years, her cognition has declined, and her behaviour has become less manageable. She is now becoming aggressive towards staff and other residents in her care home. Her GP is considering starting risperidone to help manage her aggression as behavioural measures are failing.

Which of the following is a recognised risk of risperidone?
a