MAOIs and SSRIs Flashcards
1) Outline the MoA of monoamine-oxidase inhibitors
2) list 2 MAOIs
1) MAOIs inhibit monoamine oxidase, thereby causing an accumulation of amine neurotransmitters
2) Phenelzine, Isocarboxide
what conditions are MAOIs contraindicated in? (3)
1) Cerebrovascular disease
2) Not indicated in manic phase
3) Phaeochromocytoma (rare tumor of adrenal gland)
What side-effects can MAOIs cause, and when would it need to be discontinued as a result?
1) Risk of postural hypotension and hypertensive responses
2) Discontinue if palpitations or frequent headaches occur.
1) Potentially life-threatening hypertensive crisis can develop in those taking MAOIs if they eat food containing what?
2) How long after discontinuing treatment with a MAOI should these foods continue to be avoided?
1) Tyramine-rich food or foods containing dopa (such as broad bean pods).
2) Avoid tyramine-rich or dopa-rich food or drinks with, or for 2 to 3 weeks after stopping, the MAOI.
list some common tyramine-rich food
1) Mature cheese, salami, pickled herring
2) Bovril®, Oxo®, Marmite®, yeast extract
3) Fermented soya bean extract, and some beers, lagers or wines
what are the monitoring requirements for MAOIs?
Monitor blood pressure (risk of postural hypotension and hypertensive responses)
MAOIs are associated with withdrawal symptoms on cessation of therapy. List some of the withdrawal symptoms that could occur if MAOIs are discontinued abruptly
1) Agitation, irritability, ataxia
2) Insomnia, drowsiness, vivid dreams
3) Movement disorders, cogitative impairment, and slowed speech.
4) Occasionally, hallucinations and paranoid delusions
Over what period of time should MAOIs ideally be withdrawn?
Reduced gradually over about 4 weeks, or longer if withdrawal symptoms emerge
what patient and carer advice should be given to those taking MAOIs?
1) eat only fresh foods and avoid food that are suspected of being stale or ‘going off’. Especially meat, fish, poultry or offal; game should be avoided.
2) The danger of interaction persists for up to 2 weeks after treatment with MAOIs is discontinued.
3) Avoid alcoholic drinks or de-alcoholised drinks
4) Drowsiness may affect performance of skilled tasks
Moclobemide acts by reversible inhibition of monoamine oxidase type A (RIMA).
1) How does it differ to MAOIs with regards to the interaction with tyramine rich foods?
2) How should the dose of this drug be adjusted if given with cimetidine?
1) less potentiation of the pressor effect of tyramine than the traditional (irreversible) MAOIs
2) Reduce dose to half or one-third of the usual dose with concurrent use of cimetidine
1) Outline the MoA of SSRIs
2) List 4 SSRIs
1) Preferentially inhibit neuronal reuptake of 5-HT from the synaptic cleft, thereby increasing its availability for neurotransmission
2) Citalopram, fluoxetine, sertraline, escitalopram
Who are SSRIs contraindicated in? (2)
1) Poorly controlled epilepsy
2) SSRIs should not be used if the patient enters a manic phase.
Who should SSRIs be used in caution with?
1) patients at heightened risk of adverse effects, e.g. epilepsy and peptic ulcer disease.
2) In young people, SSRIs have poor efficacy and are associated with an increased risk of self-harm and suicidal thoughts
3) Metabolised by the liver, dose reduction may be required in people with hepatic impairment
4) Diabetes, angle-closure glaucoma
What side effects can SSRIs cause?
1) Common: GI upset, changes in appetite and weight, chest pain, and hypersensitivity reactions e.g. rash
2) Hyponatraemia- in the elderly, may present with confusion and reduced consciousness
3) Suicidal thoughts and behaviour may be increased
4) lower the seizure threshold. Some (e.g. citalopram) can prolong the QT interval, predisposing to arrhythmias.
5) SSRIs also increase the risk of bleeding.
6) Can cause serotonin syndrome
The dose of SSRIs should reduced over at least a few weeks to avoid withdrawal symptoms. List the common symptoms associated with sudden withdrawal of SSRIs
1) GI upset, sweating
2) neurological and influenza-like symptoms
3) Sleep disturbance, fatigue,
4) Electric shock sensation in the head, neck, and spine
5) Headache
6) tinnitus
1) In general, the withdrawal effects of antidepressants occur within how many days of stopping treatment?
2) The risk of withdrawal symptoms is increased if antidepressants are stopped suddenly in which patients?
1) 5 days of stopping treatment with antidepressant drugs
2) If stopped suddenly in those taking them after regularly for 8 weeks or more
Can SSRIs be used in pregnancy, what are the risks?
1) Avoid during pregnancy unless the potential benefit outweighs the risk.
2) Risk of congenital heart defects in early pregnancy.
3) In third trimester there is a risk of neonatal withdrawal symptoms, and persistent pulmonary hypertension
Outline the signs and symptoms of an SSRI overdose
Nausea, vomiting, agitation, tremor, nystagmus, drowsiness, and sinus tachycardia; convulsions
Over what period of time should the dose of sertraline be reduced to avoid wthdrawal symptoms?
1) over about 4 weeks, or longer symptoms emerge
2) 6 months in patients who have been on long-term treatment
Outline some of the important interactions with regards to SSRIs
1) Avoid with MAOIs and other serotonergic drugs (e.g. tramadol), as they may precipitate serotonin syndrome
2) Gastroprotection considered for patients taking SSRIs with aspirin or NSAIDs- increased risk of bleeding.
3) Bleeding risk is also increased where SSRIs are co-prescribed with anticoagulants
4) Avoid use with other drugs that prolong the QT interval, such as antipsychotics
What counselling should be provided to those taking SSRIs?
1) Driving and skilled tasks
2) Do not to stop treatment suddenly as this may cause a flu-like withdrawal symptoms and sleeplessness ect.
3) Symptoms might be worse to start with and it might take up to 2 weeks before drug kicks in
