BNF Chapter 4: CNS Flashcards
What medication is an example of a hypnotic, and what is it prescribed for?
Zopiclone, prescribed for severe insomnia where all non-drug measures have failed and the insomnia is severe and disabling.
What is the maximum length of time it is recommended that hypnotics are prescribed for?
Up to 2 weeks only
Melatonin 2mg MR and Adalfex tablets are hypnotics, but have specific licensing and are not recommended in certain patient groups.
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What are the two examples of anxiolytic drugs?
Diazepam
Chlordiazepoxide
When is the only time chlordiazepoxide is licensed?
For alcohol withdrawal, under specialised services
When are benzodiazepines indicated for use in anxiety?
Short-term relief (2-4 weeks) when the anxiety is severe and disabling
Benzodiazepines and _ should not be used in combination, as there is a risk of potentially fatal respiratory depression.
Opioids
Benzodiazepines should not be used to treat generalised anxiety disorder, unless it is short-term for a crisis.
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What are some examples of first-generation antipsychotics?
Chlorpromazine
Flupentixol
Haloperidol
Sulpiride
Trifluoperazine
Zuclopenthixol
What are some examples of second-generation antipsychotics?
Amisulpride
Aripiprazole
Olanzapine
Quetiapine
Risperidone
Haloperidol poses risks in elderly patients, for the treatment of delirium. When should it be considered?
When non-pharmacological interventions are ineffective, and no contraindications are present (Parkinson’s disease and dementia with lewy bodies).
What tests should be done prior to intiating haloperidol treatment?
Baseline ECG and correction of any electrolyte disturbances ; cardiac and electrolyte monitoring should be repeated during treatment.
What potential side-effects of haloperidol should be investigated ASAP?
Extrapyramidal adverse effects, such as acute dystonia, parkinsonism, tardive dyskinesia, akathisia, hypersalivation and dysphagia.
Quetiapine MR is more expensive than standard formulations.
True or False?
True
Clozapine is a drug that can be very harmful. What are some potentially fatal risks of the drug?
Intestinal obstruction, faecal impaction and paralytic ileus. Constipation should be reported immediately.
What are some examples of antimanic drugs?
Carbamazepine
Sodium valproate
Lithium
Lithium should be prescribed by brand name. True or False?
True
Lithium patients should have a purple book.
What are the limitations on prescribing sodium valproate?
Shouldn’t be used to treat migraine and bipolar during pregnancy, or treating epilepsy during pregnancy unless there are no other effective treatments available. Valproate-containing medicines should also not be given to any female that is able to have children unless the conditions of a new pregnancy prevention programme are met.
Pregnancy Prevention Programme
Valproate-containing medicines must not be used in any
woman or girl able to have children unless the conditions of a new pregnancy prevention
programme are met. These include:
- an assessment of each patient’s potential for becoming pregnant
- pregnancy tests before starting and during treatment as needed
- counselling about the risks of valproate treatment and the need for effective contraception
throughout treatment - a review of ongoing treatment by a specialist at least annually
- introduction of a new risk acknowledgement form that patients and prescribers will go through
at each such annual review to confirm that appropriate advice has been given and understood.
..
What risks does valproate exposure in utero pose?
High risk of developmental disorders and congenital malformations.
What are some examples of TCAs?
Amitriptyline
Nortriptyline
Lofepramine
Trazodone
What is amitriptyline primarily used for?
Neuropathic pain
When is pregabalin classed as ‘green’ for treating generalised anxiety disorder?
When initiated by a specialist, after SSRIs or venlafaxine have been ineffective, poorly tolerated or are clinically inappropriate.
Which groups of patients may have a higher risk of repiratory depression whilst using pregabalin?
-Patients with compromised respiratory function
-Patients with repiratory or neurological disease
-Patients with renal impairment
-Patients using opioids/other CNS depressants
-People over 65
Pregabalin is safe in pregnancy.
True or False?
False
It slightly increases the risk of major congenital malformations; should be avoided in pregnancy unless clearly necessary.
Why are amitriptyline and imipramine preferred as depression treatments over nortriptyline?
They are more cost-effective.
Why is Dosulepin classified as ‘Do Not Prescribe’ for new patients?
Extremely dangerous in overdose, and not recommended for depression.
Moclobemide 150mg and 300mg are monoamine-oxidase inhibitors- it poses little dietary restrictions and few interactions
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What are some examples of SSRIs?
Citalopram
Fluoxetine
Sertraline
Vortioxetine
The SSRI that is first-line depends on the patient that it is for!!
Which SSRI would be first-line for a breast-feeding patient?
Sertraline
SSRI’s and Upper GI Bleeds
- SSRIs can increase upper GI bleed risk, especially when used alongside _
- If a patient is particularly high risk of an upper GI bleed then a gastro-protective agent could be considered.
NSAIDs
What is the maximum daily dose of citalopram in adults? What about in the elderly (Over 65) and those with reduced hepatic function?
Adults- 40mg
Elderly and reduced hepatic function- 20mg
When would citalopram use be completely contraindicated?
In patients with known QT interval prolongation or congenital long QT syndrome, or if the patient is using other medicines that are known to prolong QT interval
When would citalopram use be cautioned?
In patient at higher risk of developing Torsade de Pointes, including those with congestive heart failure, recent MI, bradyarrhythmias, or a predisposition to hypokalaemia or hypomagnesaemia due to illness or drug therapy.
How should the dose of citalopram oral drops be stated?
Stated in drops, not ml.
Fluoxetine can be used in children and adolescents. CAHMS will initate treatment and then the prescribing will be handed over to primary care. Fluoxetine 20mg dispersible tablets are cost-effective if the patient has swallowing difficulties. Sertraline is second-line after consultant/specialist initiation.
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Vortioxetine is licensed for treating major depressive episodes.
SSRIs and SNRIs (venlafaxine) can increase _ risk; some data suggests that the use of these antidepressants in the last month before birth can increase the risk of postpartum haemorrhage. Consider risk vs benefit.
Bleeding
Other antidepressant drugs include mirtazapine, duloxetine and venlafaxine.
In what patient groups should venlafaxine be avoided?
Patients with pre-existing heart disease and anyone with uncontrolled or untreated hypertension. Review BP after initiation, dose increase and annually; if raised then only continue venlafaxine if BP under control and alternative antidepressant is unsuitable.
What is CNS stimulant drug example and what is it used for?
Modafinil 100mg and 200mg tablets- narcolepsy and narcolepsy secondary to parkinsons disease.
What are some examples of drugs that can be used to treat ADHD?
Methylphenidate
Lisdexamfetamine
Dexamfetamine
Atomoxetine
Guanfacine
Why should methylphenidate be prescribed by brand name, and should be cautioned if switching patients between different long-acting formulations of the drug?
Different formulations have different dosing frequencies, food instructions, amounts and timing. Specific dosing recommendations for each formulation should be followed.
What drug can be used in the treatment of obesity?
Orlistat 120mg capsules
What drugs can be used to treat nausea and vertigo?
Metoclopramide
Domperidone
Cyclizine
Prochlorperazine
Cinnarizine
Betahistine
Metoclopramide
- For adults, the maximum dose in 24 hours is _mg (or 0.5mg per kg bodyweight). The usual dose
is 10mg three times a day and should only be prescribed for short-term use (up to 5 days) - Off label use of metoclopramide is recognised as standard practice in palliative medicine. JAPC
recognises that long term use of metoclopramide may be appropriate in some patients given
orally/parentally - Use in patients under 20 years of age is restricted and likely to cause dystonic reactions
30
What is the maximum metoclopramide dose in 24h for an adult?
30mg (or 0.5mg per kg of bodyweight). 10mg TDS is the usual dose, and should only be used for up to five days
Domperidone
Domperidone may be associated with a small increased risk of serious ventricular arrhythmia or
sudden cardiac death. These risks may be higher in patients older than 60 years and in patients
who receive daily oral doses of more than 30 mg.
* For adults the maximum dose in 24 hours is 30mg. The duration of treatment should not
usually exceed one week.
* Domperidone is preferred in patients where the risk of dystonic reactions is high i.e., young
women, children, the elderly, and those with Parkinson’s disease.
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Why is domperidone no longer licensed for children under 12?
Lack of efficacy
What specifically is prochlorperazine used for and in what patient group should it be avoided and why?
Vertigo. Should be avoided in the elderly if possible due to extrapyramidal side-effects
Haloperidol is recommended to control opiate induced vomiting. What dose should be used?
1.5mg orally once or twice daily , or 2.5mg IM to stop active vomiting.
Nausea and Vomiting in Pregnancy
- Reassure women that mild to moderate nausea and vomiting are common in pregnancy and likely
to resolve before 16-20 weeks. - For pregnant women with mild-to-moderate nausea and vomiting who prefer a non-pharmacological option, suggest that they try ginger.
- When considering pharmacological treatments for nausea and vomiting in pregnancy, discuss the
advantages and disadvantages of different antiemetics with the woman. Take into account her
preferences and her experience with treatments in previous pregnancies. - For pregnant women with nausea and vomiting who choose a pharmacological treatment, offer an
antiemetic.
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Paracetamol is the simple analgesic of choice; co-codamol and co-dydramol are listed by the BNF as being less suitable.
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Why should effervescent analgesics be avoided unless someone has genuine swallowing difficulties?
They have a high sodium content and are associated with significantly increased odds of adverse cardiovascular events compared with standard formulations (does not apply to dispersible aspirin)
What patient groups may be at an increased risk of experiencing analgesic toxicity at therapeutic doses?
Patients with a bodyweight under 50kg
Patients with risk factors for hepatotoxicity, such as alcoholics, malnourishment, chronic dehydration, frailty etc)
Use clinical judgement:
- Patient with risk factors: consider reducing total daily dose of paracetamol to max 3g in 24h
-Patient under 50kg: consider reducing dose using 15mg/kg (max 60mg/kg) and a max of 2g in 24 hours.
Opioid Analgesics: Benzodiazepines and Opioids
Risk of potentially fatal respiratory
depression. Only prescribe together if there is no alternative and closely monitor patients for signs of
respiratory depression.
At the end of treatment, taper dosage slowly to reduce the risk of withdrawal effects. Consider the possibility of hyperalgesia if a patient on long-term opioid therapy presents with increased sensitivity to pain.
Long-term (>3months) use in non-cancer pain, even at therapeutic doses, carries an increased risk of dependence and addiction. Before prescribing opioids, discuss with the patient the risks and features of tolerance, dependence, and addiction, and agree together a treatment strategy and plan for end of treatment.
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What are some examples of ‘weak’ opioid analgesics?
Codeine phosphate
Dihydrocodeine
Tramadol
Codeine should only be used to relieve acute moderate pain, if it cannot be relieved by other painkillers such as paracetamol and ibuprofen. How old must the patient be?
12 years plus
Tramadol
-Consider for neuropathic pain only if acute rescue therapy is needed, as long-term use is not advised
-Has a high incidence of ADRs and drug interactions
-Schedule _ CD- Rx is only valid for 28 days and for 30 days treatment (30 days unless exceptional circumstances)
3
For Schedule 2, 3 and 4 CD’s, what is the maximum prescription validity length and how long of a supply should be prescribed as a maximum (except in excepional circumstances)?
28 days validity, and no longer than 30 days course length in one go
What are some examples of ‘strong’ opioids?
Morphine sulphate
Oxycodone
Fentanyl
Buprenorphine
Morphine sulphate is first-line for the prescribing of strong opioids. What are the different formulations?
-Modified-release capsules, such as Zomorph
-Immediate release tablets, such as Sevredol
-Oral solution 10mg/5ml
-Injection Ampoules 10mg/ml
Oxycodone or Fentanyl are the second-line options for strong opioid prescribing. What formulation options are there?
Oxycodone:
-Modified release tablets
-Immediate release capsules
-Oral solution 5mg/5ml
Fentanyl:
-Patch
Whilst a patient is on regular morphine, what else should they be prescribed?
A laxative
An anti-emetic if appropriate
Fentanyl
Always fully inform patients and their caregivers about directions for safe use for fentanyl patches,
including the importance of:
- not exceeding the prescribed dose
- following the correct frequency of patch application, avoiding touching the adhesive side of
patches, and washing hands after application - not cutting patches and avoiding exposure of patches to heat including via hot water (bath,
shower) - ensuring old patches are removed before applying a new one
- following instructions for safe storage and properly disposing of used patches or those which
are not needed.
Remind patients (or caregivers) to:
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* Follow the correct frequency of patch application, avoiding touching the adhesive side of patches,
and washing hands after application. Remove old patches before applying a new one.
* Avoiding exposure of patches to heat including via hot water (bath, shower)
* Follow instructions for safe storage and properly disposing of used patches or those which are not
needed. After use, patches should be folded so that the adhesive side of the patch adheres to itself
and then placed back into the original sachet.
* Be aware of the signs and symptoms of fentanyl overdose (e.g., difficulty/ shallow breathing;
tiredness; extreme sleepiness/ sedation; feeling faint, dizzy or confused) and seek medic
.
What are some signs of fentanyl overdose?
Difficulty /shallow breathing, tiredness, sedation, feeling faint, dizziness and confusion.
When is the only time fentanyl patches should be considered for a patient?
When the patient is on a stable dose of opioid but they are unable to swallow/comply with oral medication.
Buprenorphine
- Buprenorphine patches are classified as GREY - the patches should be prescribed by brand as the
frequency to be applied may vary between brands - Buprenorphine patches at lower doses are broadly as effective as codeine or tramadol but much more
expensive. - The patches are unsuitable in acute or unstable pain due to the need for slow titration of doses; it may
take up to 72 hours to achieve a stable blood level after a change in dose. - The preferred cost-effective brand for low dose (7 day) patch is Reletrans
- Higher strength patches are also available, but the bioavailability and application varies between
brands. Different brands are not interchangeable. Check individual SPC carefully. - The preferred cost-effective high strength brand (replace after 96 hours) is Relevtec
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Why is buprenorphine not suitable for acute pain?
It can take up to 72 hours to achieve a stable blood level after a change uin dose- does not provide quick relief
What are some drugs that can be used to treat migraines?
Aspirin
Ibuprofen
Paracetamol
Sumatriptan
Zolmitriptan
Prochlorperazine (if N&V)
Metoclopramide (N&V)
Triptans:
Should not be taken by people who have: Uncontrolled or severe hypertension; Cardiovascular disease, or are at high risk of cardiovascular disease; Coronary vasospasm (including Prinzmetal’s angina).
* For all triptans there is good evidence that a second dose is effective for relapse but very little to
show that it is the most appropriate treatment.
* All triptans except intranasal sumatriptan are unlicensed for use in children under 18. 5HT1
receptor agonists for children (aged 12-17) should be referred and initiated by a specialist.
Sumatriptan and zolmitriptan oral formulations are treatment options (see BNF for children).
* Where triptans are indicated for acute migraine NICE CG150 recommends the use of combination
therapy with a triptan and an NSAID, or a triptan and paracetamol, for first-line treatment of acute
migraine with or without aura.
* if vomiting restricts oral treatment, consider a non-oral formulation (such as sumatriptan nasal
spray or subcutaneous sumatriptan.
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What does NICE recommend for the first-line treatment of acute migraine with or without aura?
A triptan (sumatriptan or zolmitriptan) with an NSAID or paracetamol
What medications can be used for the prophylaxis of migraines?
Propranolol 80-160mg daily (first-line)
Topiramate 50-100mg daily (second-line)
Amitriptyline 25-150mg daily (second-line)
Migraine Prophylaxis
- Consider prophylaxis if migraine is disabling and reducing quality of life, e.g., frequent attacks (>1 per
week on average) or prolonged severe attacks. Start at low dose and gradually increase according to
efficacy and tolerability. - If the patient responds well to prophylactic treatment a trial of gradual drug withdrawal should be
considered after six months to one year. - Good response is a 50% reduction in severity and frequency of attacks; treatment failure is a lack of
response to the highest tolerated dose used for 3 months. - Candesartan (16 mg daily) can be considered as a prophylactic treatment for patients with
episodic or chronic migraine.
-Metoprolol at a dose of 100mg-200mg daily in divided doses is a suitable licensed alternative if
propranolol cannot be tolerated; Nortriptyline is 2nd line option (less cost effective) only to be used if
amitriptyline is effective but patient unable to tolerate side effects.
- Verapamil may be considered for prophylactic treatment during a bout of cluster headache. If
unfamiliar with its use for cluster headache, seek specialist advice before starting verapamil, including
advice on electrocardiogram monitoring.
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What is considered a good response to migraine prophylaxis treatment?
Good response is a 50% reduction in severity and frequency of attacks; treatment failure is a lack of
response to the highest tolerated dose used for 3 months.
Topiramate as Migraine Prophylaxis
-Advise women and girls of childbearing potential that topiramate is associated with a risk of foetal
malformations and can impair the effectiveness of hormonal contraceptives.
-Pregnancy testing should be performed before initiating, and a highly effective contraceptivemethod advised.
- EMA March 2018 recommends a ban on the use of valproate-containing medicines for migraine or
bipolar disorder during pregnancy, and a ban on treating epilepsy during pregnancy unless there is no
other effective treatment available. Valproate-containing medicines must not be used in any woman or girl able to have children unless the conditions of a new pregnancy prevention programme are met.
What is first-line for migraine prophylaxis?
Propranolol
What are some examples of antiepileptic medications?
Clonazepam
Carbamazepine
Ethosuximide
Gabapentin
Lacosamide
Lamotrigine
Levetiracetam
Oxcarbazepine
Phenobarbital and other barbiturates
Phenytoin
Pregabalin
Sodium valproate
Topiramate
Zonisamide
What are the three risk-based categories that antiepileptics are divided into?
Category 1: prescribers are advised that patients receiving treatment for epilepsy are maintained
on the same manufacturer.
Category 2: continuity of manufacturer is based on clinical judgement taking into account factors such as seizure frequency and treatment history
Category 3: it is usually unnecessary to ensure a specific manufacturer
What anti-epileptics fall into category 1 of risk-based categories?
carbamazepine
phenytoin
phenobarbital
primidone
What antiepileptics fall into category 2 of the risk-based categories?
clobazam
clonazepam
eslicarbazepine
lamotrigine
oxcarbazepine
perampanel
retigabine
rufinamide
topiramate
valproate
zonisamide
What antiepileptics fall into category 3 of the risk-based categories?
ethosuximide
gabapentin
lacosamide
levetiracetam
pregabalin
tiagabine
vigabatrin
Antiepileptic Drugs in Pregnancy
- Lamotrigine and Levetiracetam are the safer of the antiepileptic medicines in pregnancy.
- Women using antiepileptic drugs who are planning to become pregnant should be offered folic acid
5mg daily before any possibility of pregnancy. - Urgently refer women who are planning to become pregnant for specialist advice on their
antiepileptic treatment. - These are usually initiated by specialist. GPs using antiepileptic drugs for other indications must
carefully consider the risk and benefit.
-There is an increased risk of teratogenicity associated with the use of antiseizure medications
(reduced if treatment is limited to a single drug). Ensure adequate contraception. Those who wish to
become pregnant or become pregnant should be referred to an appropriate specialist for advice.
-Be aware that long-term treatment with some antiseizure medications (such as carbamazepine,
phenytoin, primidone and sodium valproate) is associated with decreased bone mineral density and
increased risk of osteomalacia.
-Be aware that oestrogen-containing hormonal contraceptives and hormone replacement therapy can
impair the effectiveness of lamotrigine.
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What are the safest antiepileptics to be used during pregnancy?
Lamotrigine and Levetiracetam
Which antiepileptic medications are associated with decreased bone mineral density and osteomalacia when used long-term?
Carbamazepine
Phenytoin
Primidone
Sodium valproate
Before a woman of childbearing potential can be initiated on valproate, the conditions of a new pregnancy programme must be met. What are these conditions?
-an assessment of each patient’s potential for becoming pregnant
- pregnancy tests before starting and during treatment as needed
- counselling about the risks of valproate treatment and the need for effective contraception
throughout treatment
- a review of ongoing treatment by a specialist at least annually
- introduction of a new risk acknowledgement form that patients and prescribers will go through
at each such annual review to confirm that appropriate advice has been given and understood.
Children exposed to valproate in utero are at high risk of what?
Developmental disorders and congenital malformations
Why should topiramate tablets be prescribed rather than capsules?
Capsules are more expensive
What are the risks associated with topiramate in pregnancy?
Foetal malformations and can impair the effectiveness of hormonal contraceptions
What is Midazolam used for?
The management of convulsive seizures in the community
Midazolam Buccal (Buccolam)- pre-filled syringe 2.5mg/0.5ml, 5mg/1ml, 7.5mg/1.5ml, 10mg/2ml
-Derbyshire has moved to one preferred buccal midazolam product (Buccolam), for use in both adults
(off-licence use) and children (licensed use).
- Epistatus (10mg/1ml) is classified as Grey, when initiated by out-of-area providers.
- Existing patients on Epistatus should be reviewed by the specialist and switched to the
recommended Buccolam preparation at their next review and the patients care plan should be
updated accordingly. Do not stop the Epistatus abruptly, without the patient receiving training for
the Buccolam preparation. In line with NICE guidance diazepam rectal tubes 2.5, 5, 10mg are no
longer recommended first line for seizure control.
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What drugs are used in parkinsonism and related disorders?
-Ropinirole (Ipinnia XL)
-Pramipexole MR (second-line)
-Carbidopa/entacapone/levodopa combination (Stanek and Sastravi)
-Procyclidine (Kemadrin)