CNS Flashcards
Treating (attenuating) alcohol withdrawal symptoms
Long acting benzodiazepine (e.g. Chlordiazepoxide/diazepam), carbamazepine or clomethiazole (inpatient only)
How to treat alcohol withdrawal seizures
Fast acting benzodiazepine e.g. Lorazepam
What is delirium tremens characterised by
Agitation, confusion, paranoia and visual and auditory hallucinations
Treating alcohol dependence
Psychological intervention, acamprosate, oral naltrexone
Wernickes treatment
Parenteral and then oral thiamine
Dental anaesthetics
Lidocaine, mepivicaine (can be used without adrenalin in patients with heat problems), prilocaine
Why are neuromuscular blocking drugs used
To provide relaxation and prevent reflex muscle movements (facilitating tracheal intubation)
Propofol characteristics
Rapid recovery, less hangover effect
Nitrous oxide use
Maintaining anaesthesia for analgesia
NO and air pressure
Increased pressure in closed spaces so dangerous in patients with no pneumothorax, intracranial air, underwater dive, intraocular injection
Treating musculoskeletal pain
Non-opioid, paracetamol, aspirin, NSAIDS
Visceral pain treatment
opioids
Pain medication to avoid in sickle cell crisis
Pethidine, as accumulation of a neurotoxic metabolite can precipitate seizures
Oral mucosal pain
Benzydamine hydrochloride mouthwash or spray until cause dealt with
General dental pain relief treatment
NSAIDS (paracetamol for antipyretic effect)
Dental pain and opioids
Opioids are relatively ineffective
Dysmenorrhoea treatment
Paracetamol, NSAID, antiemetic if needed, antispasmodics (alverine citrate)
Naproxen Dysmenorrhoea/MSK Pain regimen
Initially 500 mg, then 250 mg every 6–8 hours as required, maximum dose after the first day 1.25 g daily.
Aspirin pain indications
Headache, transient musculoskeletal pain, dysmenorrhoea, and pyrexia
Pros and cons of enteric aspirin
Slow onset, so unsuitable for single dose analgesic use but prolonged action may be useful for night pain, less gastric irritation
Nefopam indication and regumen
Initially 60 mg(30mg in elderly) 3 times a day, adjusted according to response; usual dose 30–90 mg 3 times a day. Moderate pain.
Issue with caffeine in analgesic preparations
Withdrawal may result in headache
Morphine contraindications
raised intracranial pressure, respiratory depression, head injury,
Morphine side effects
appetite decreased; asthenic conditions; gastrointestinal discomfort; insomnia; neuromuscular dysfunction
Buprenorphine unique attribute
Opioid agonist and antagonist, naloxone only partially reverses
Buprenorphine relative to morphine
Longer duration, sublingually 6-8 hours
Why is diamorphine used in palliative care
Less nausea and hypotension, greater solubility so smaller volumes required in emaciated patients
Methadone vs morphine
Less sedating, longer duration
Oxycodone vs morphine
Similar so used second line
Pethidine vs morphine
Short acting, less constipating, less potent, used in labour but morphine preferred for obstetric pain
Tapentadol MOA (vs morphine)
Inhibits noradrenaline and opioid agonist, has less NV, constipation
Tramadol MOA
Opioid and serotonergic and adrenergic pathways inhibitor
When is codeine used
When paracetamol and ibuprofen are ineffective
Codeine vs dihydrocodeine
Similar, high doses of dihydro may provide more pain relief but more nausea and vomiting too
Meptazinol indication
Moderate to severe pain
When are antidepressants used
Moderate to severe depression (mild depression but history of moderate/severe depression)
Different Antidepressant classes
MAOI, SSRI, TCA
Why/when is electroconvulsive treatment required in severe depression
There may be a 2 week interval before antidepressant action takes place, the delay may be hazardous or intolerable
What may occur during first few weeks of treatment
Increased potential for agitation, anxiety and suicidal ideation
SSRI vs other antidepressants
Safer in overdose than others, sertraline can be used in unstable angina/recent MI, are less sedating and have less antimuscarinic and cardiotoxic effects than TCA
TCA vs other antidepressants
Similar efficacy to SSRIs, more side effects leading to discontinuation and toxicity in overdose is problematic
Antidepressant monitoring at initiation frequency
Review every 1-2 weeks at the start
How long should antidepressants be used for before considering a switch
At least 4 weeks (6 weeks in elderly) ( if there is a partial response continue for further 2-4 weeks)
What to do for patients following remission
Antidepressant treatment continued at same dose for at least 6 months (12 in elderly or receiving treatment for GAD)
What to do for patients with history of recurrent depression
Maintenance treatment for at least 2 years
Common side effect amongst antidepressants
Hyponatraemia (particularly elderly potentially due to secretion of antidiuretic hormone)
What class if antidepressants is hyponatraemia most common in
SSRIs
When to consider hyponatremia in those taking antidepressants
Drowsiness, confusion, convulsions
Serotonin syndrome cause
excessive central and peripheral serotonergic activity
When does serotonin syndrome occur
Hours/days following initiation/dose escalation/overdose of serotonergic drug or replacement without a washout particularly when the first drug is irreversible MOAI/long half life
Symptoms of serotonin syndrome
Neuromuscular hyperactivity, autonomic dysfunction, altered mental state
Altered mental state
Agitation, confusion, mania
Autonomic dysfunction
Tachycardia, blood pressure, hyperthermia, diaphoresis, shivering, diarrhoea
Neuromuscular hyperactivity
Tremor, hyperreflexia, clonus, myoclonus, rigidity
Treating serotonin syndrome
Withdrawal of serotonergic medication, supportive care and specialist advice
What to do if failure to respond to SSRI
Increase SSRI dose or switch to different SSRI/mirtazapine
Second line antidepressant treatment
Mirtazapine, lofepramine, moclobemide, reboxetine
Mirtazapine class
presynaptic alpha2-adrenoreceptor antagonist which increases central noradrenergic and serotonergic neurotransmission.
Venlafaxine class
A serotonin and noradrenaline re-uptake inhibitor.
Lofepramine class
TCA
Moclobemide class
MAOi
When is venlafaxine used
Severe depression
What to do if failure to respond to second line antidepressant
Different antidepressant class used, augmenting agent e.g. Lithium, aripiprazole, olanzapine, quetiapine, risperidone (all except lithium unlicensed) or electroconvulsive therapy
Managing acute anxiety
Benzodiazepine or buspirone
Chronic anxiety length
More than 4 weeks
Treating chronic anxiety
Antidepressant
How to overcome antidepressant not working initially when treating anxiety
Benzodiazepine given
How to treat GAD
Psychological treatment before initiating an antidepressant
Antidepressants used in anxiety
SSRI e.g. Escitalopram, paroxetine, sertraline (unlicensed), SNRI e.g. Duloxetine and venlafaxine , pregabalin if both classes fail
Treating Panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, and phobic states such as social anxiety disorder a
SSRIs first line. Second line: clomipramine (ocd/panic) moclobemide (sad) imipamine (panic)
TCA MOA
Block the re-uptake of both serotonin and noradrenaline, although to different extents
TCAs with sedative properties
Amitriptyline hydrochloride, clomipramine hydrochloride, dosulepin hydrochloride, doxepin, mianserin hydrochloride, trazodone hydrochloride, and trimipramine.
TCAs with less sedative properties
Imipramine hydrochloride, lofepramine, and nortriptyline.
What TCA type to use for agitated anxious patients
Sedative
What percent of patients does TCA not work on
10-20% so use sufficiently high dose
MAOi and interaction avoidance
Other antidepressant should not be started 2 weeks after treatment with MAOis (3 weeks for clomipramine or imipramine)
When can you start MAOi after another MAOi
at least 2 weeks after a previous MAOI has been stopped (then started at a reduced dose)
When can you start MAOi after TCA
at least 7–14 days after a tricyclic or related antidepressant (3 weeks in the case of clomipramine or imipramine) stopped
When can you start MAOi after SSRI
at least a week after an SSRI or related antidepressant (at least 5 weeks in the case of fluoxetine) has been stopped
Who responds best to MAOi
Phobic patients and depressed patients with atypical, hypochondriacal, or hysterical features
TCA and the elderly
STOPP in those with dementia, narrow angle glaucoma, cardiac abnormalities, urinary retention history, prostatim, and if first ;ine
Isocarboxazid and phenelzine risk
Hepatotoxicity (all MAOi)
MAOi monitoring
Blood pressure
MAOi counselling points
Patients should be advised to eat only fresh foods and avoid food that is suspected of being stale or ‘going off’. This is especially important with meat, fish, poultry or offal; game should be avoided.
Avoid alcohol
Tyramine-rich food
Mature cheese, salami, pickled herring, Bovril®, Oxo®, Marmite® or any similar meat or yeast extract or fermented soya bean extract, and some beers, lagers or wines
Foods containing dopa
Broad bean pods
Contributions to hypertensive symptoms when on MAOi
Tyramine rich foods and dopa containing foods
ADHD characteristics
Hyperactivity, impulsivity, inattention leading to social/educational/occupational difficulties
Non-drug ADHD treatment
Balanced diet, good nutrition, regular exercise, environmental modifications, lighting , noise, reducing distraction, shorter periods of focus with movement breaks
ADHD first line
Lisdexamfetamine, methylphenidate 6-week trial
When is dexamfetamine used in ADHD
If the patient has a beneficial response from lisdexamfetamine but can’t tolerate longer duration
Why is MR ADHD treatment used
Pharmacokinetic profile, convenience, improved adherence, reduced risk of drug diversion, no need to take at work
Drugs that shouldn’t be generally stopped before surgery
Antiepileptics, antiparkinsonian drugs, antipsychotics, anxiolytics, bronchodilators, cardiovascular drugs, glaucoma, immunosuppreants, thyroid/antithyroid
When should lithium be stopped before a surgery
24 hours before if major, can continue if minor
ACE/ARB and surgery
Severe hypotension after anaesthesia so discontinue 24 hours before surgery
Anaesthesia and corticosteroids
Anaethesists should be informed of corticosteroid use including inhalers because blood pressure may drop if there is no corticosteroid during anaesthesia
When should potassium sparing diuretics be stopped before surgery
The morning due to hyperkalaemia arising from renal impairment
Substitution therapy missed doses repercussions
Missing 3 days = reduce dose due to overdose risk, missing 5 days = restart, especially buprenorphine
Why is buprenorphine preferred to methadone
Less sedating, interactions, easier dose reductions, lower overdose risk, alternate days at higher doses, shorter drug-free period before naltrexone induction to prevent relapse, titrate more rapidly
When does buprenorphine precipitated withdrawal occur
Other opioid agonists in circulation , occurs 1-3 hours within first buprenorphine dose
What is given when symptoms of precipitated withdrawal are severe
Lofexidine adjunctive therapy
Pregnancy and opioid substitution
Should be done as benefits outweigh risks, maintenance regimen, withdrawal not recommended in first and third trimester
Symptomatic opioid withdrawal treatment
Loperamide for diarrhoea, mebeverine for stomach cramps, metoclopramide for nausea, short acting benzo for insomnia
Opioid antagonist
Naloxone
Naltrexone action
Precipitates withdrawal symptoms , prevents relapse
Sedation for dental procedures
Diazepam and temazepam, effective anxiolytics, conscious sedation
Treating early stages of agitation/behavioural disturbance (mania)
Benzodiazepine
Antipsychotics used to treat acute mania/hypomania
Olanzapine 5-10mg, quetiapine, risperidone 2mg
Long term management of bipolar
Olanzapine in those that responded to it in a manic episode(monotherapy or with lithium/valproate)
Preventing bipolar
Lithium, (olanzapine, quetiapine) Carbamazepine if unresponsive to alternatives and have 4/more episodes a year), valproate also used
Use of valproate in bipolar
Treatment of manic episodes and prophylaxis of bipolar can add or switch to lithium/olanzaine if ineffective, can increase valproate dose during episodes of mania
Role of lithium in bipolar
Prophylaxis and treatment of mania, hypomania and depression in bipolar disorder (manic-depressive disorder), and in the prophylaxis and treatment of recurrent unipolar depression. Can be used concomitantly with antidepressants.
How long does it take for full lithium prophylactic effect
6-12 month window
Treating aggressive or self harming behaviour
Lithium
Positive symptoms
Thought disorder, hallucinations, and delusions
Negative symptoms
Apathy , social withdrawal
Antipsychotic and positive/negative
Relieve positive symptoms and prevent relapse
Negative symptoms treatment
Second gen antipsychotic
1st generation antipsychotic MOA
Blocks dopamine D2 brain receptors, not selective
Group 1 phenothiazine drugs and characteristics
Chlorpromazine, levomepromazine, and promazine,
pronounced sedative effects and moderate antimuscarinic and extrapyramidal side-effects
Group 2 phenothiazine drugs and characteristics
Least EPS, moderate sedative effects, pericyazine, more antimuscarinic
Group 3 phenothiazine drugs and characteristics
Most EPS, few sedative, few antimuscarinic, fluphenazine decanoate, perphenazine, prochlorperazine, and trifluoperazine,
What group of phenothiazine’s do butyrophenones e.g. Haloperidol clinically resemble
3
Second gen antipsychotics characteristic
Atypical, range of receptors, distinct profiles
Antipsychotics in the elderly
Not used in mild/moderate psychotic symptoms, initial dose half adult dose or less, review regularly