ssri_flashcards

Question

A 24-year-old woman presents to the emergency department complaining of feeling sweaty and confused. These symptoms began around 12 hours ago. On examination, the patient is disorientated and rigid. Her temperature is 38.6ºC. On further questioning, she tells you she had consumed recreational drugs. The patient's past medical history includes depression and she has been on sertraline long-term. She has been started on selegiline after her depression symptoms worsened. She also has asthma and uses a salbutamol reliever regularly. What may have led to the patient's presentation? Cannabis Cocaine Heroin Salbutamol Selegiline

Answer 1

Selegiline SSRIs and MAOIs should never be combined as there is a risk of serotonin syndrome Important for meLess important Selegiline is the correct answer. This patient is presenting with signs and symptoms of serotonin syndrome. Serotonin syndrome is a life-threatening condition associated with increased serotoninergic activity in the central nervous system. Features include mental status changes, autonomic hyperactivity (hyperthermia, sweating) and neuromuscular abnormalities (hyperreflexia and rigidity). Patients should never be given both SSRIs and monoamine oxidase inhibitors such as selegiline as both can increase serotonin levels excessively. Cannabis is incorrect. This drug is not an identifiable cause of serotonin syndrome as it does not interact with the serotonin system. Serotonin accumulation is the culprit of the development of serotonin syndrome, making this option incorrect. Cocaine is incorrect. This drug is similarly not an identifiable cause of serotonin syndrome given the fact it does not interact with the serotonin system. Cocaine primarily affects the dopamine and norepinephrine systems in the brain, leading to its stimulating effects. Heroin is incorrect. This drug is also not an identifiable cause of serotonin syndrome. Heroin primarily affects the opioid receptors in the brain, leading to its pain-relieving and sedative effects. Salbutamol is not correct. Salbutamol does not elevate serotonin levels leading to toxicity. Other medications or substances that can lead to serotonin syndrome include St. John's wort, tramadol and amphetamines.

Answer 2

Diarrhoea Gastrointestinal side-effects such as diarrhoea are seen in SSRI discontinuation syndrome Selective serotonin reuptake inhibitor discontinuation syndrome can present with a wide variety of symptoms including diarrhoea, vomiting and abdominal pain.

Answer 3

Sumatriptan Triptans should be avoided in patients taking a SSRI The correct answer is sumatriptan. The patient presents with symptoms indicative of serotonin syndrome, such as agitation, restlessness, confusion, muscle rigidity, hyperreflexia, dilated pupils and flushed skin. Serotonin syndrome is a consequence of excessive serotonergic accumulation in the central nervous system and can range from mild to life-threatening. It often results from the concurrent use of multiple serotonergic agents. Given that the patient was already on an SSRI (escitalopram), it is likely that sumatriptan has precipitated these symptoms. Sumatriptan is a triptan used in migraine management; it acts as a serotonin receptor agonist. When combined with escitalopram's selective inhibition of serotonin reuptake, the risk for serotonin syndrome increases, making sumatriptan the most probable cause. It is worth noting that escitalopram is also notorious for QTc prolongation and, while not directly relevant to this presentation, it should be kept in mind for any unwell patient taking this medication as it most likely warrants an ECG as part of investigations. Aripiprazole is an antipsychotic drug which does not notably increase the risk of inducing serotonin syndrome when co-prescribed with escitalopram. The British National Formulary lists its association with this condition as 'frequency not known'. However, there is an increased risk of hyponatraemia when used together with SSRIs. Diclofenac, a non-steroidal anti-inflammatory drug (NSAID), should be prescribed cautiously in patients on escitalopram due to an elevated bleeding risk. However, it has not been implicated in increasing the likelihood of developing serotonin syndrome. Paracetamol is not associated with an increased risk of serotonin syndrome. It is a widely used analgesic and antipyretic agent without known serotonergic properties. Risperidone, another antipsychotic medication, similarly has no significant evidence suggesting it causes serotonin syndrome when co-administered with escitalopram. Nonetheless, there exists a potential for heightened hyponatraemia risk under such combination therapy.

Answer 4

**Fluoxetine + omeprazole** SSRI + NSAID = GI bleeding risk - give a PPI Selective serotonin reuptake inhibitors (SSRIs) are considered the first-line pharmacological treatment for patients presenting with moderate depression. This patient is currently taking a nonsteroidal anti-inflammatory drug (NSAID) on a regular basis to manage his ankylosing spondylitis, which increases the risk of gastrointestinal (GI) bleeding. Consequently, when initiating an SSRI in this scenario, it is prudent to co-prescribe a proton pump inhibitor (PPI) to mitigate this risk. Thus, fluoxetine + omeprazole represents the most appropriate management strategy. While sertraline is another effective SSRI for treating depression, prescribing it without concomitant PPI protection would elevate the patient's risk of GI bleeding. As such, it is not considered a suitable option in this context. Initiating two antidepressant medications simultaneously is generally discouraged; therefore, commencing treatment with fluoxetine + amitriptyline would be inappropriate. Moreover, this combination does not address the potential increase in GI bleed risk associated with NSAID use. Mirtazapine, an atypical antidepressant, is not typically recommended as a first-line agent for moderate depression and hence is not the preferred choice here. Although a self referral to local NHS talking therapies might be advisable for individuals with mild depression, it would not be fitting for this patient given his PHQ-9 score indicative of moderate depression and his inclination towards pharmacotherapy. In such instances, counselling or other forms of psychotherapy should ideally complement rather than replace antidepressant therapy

Answer 5

Diarrhoea Gastrointestinal side-effects such as diarrhoea are seen in SSRI discontinuation syndrome Important for meLess important The salient point here is to note the use of citalopram. Stopping a salbutamol inhaler and paracetamol suddenly are not likely to lead to any side effects. Stopping a selective serotonin reuptake inhibitor (SSRI), such as citalopram, abruptly will lead to discontinuation symptoms. From those listed, by far, the most likely is diarrhoea, as gastrointestinal side-effects are generally common with SSRI discontinuation syndrome. To avoid this, SSRIs should gradually be tapered. A blunted affect is unlikely to occur as a result of sudden discontinuation. This is often a side effect of antidepressants themselves. Discontinuation sometimes leads to the opposite - emotional lability and visible mood swings. Cyanopsia, or blue-tinted vision, is not known to occur with SSRI discontinuation. It is a recognised side effect of some drugs, including sildenafil. Hypertension has been reported in a few cases upon discontinuation of SSRIs, but diarrhoea and gastrointestinal symptoms are far more likely. It is more common with sudden discontinuation of beta-blockers. Weight loss, rather than weight gain, is often reported upon sudden discontinuation of SSRIs.

Answer 6

**Fluoxetine** Fluoxetine is the SSRI of choice in children and adolescents The correct answer is Fluoxetine. According to the UK National Institute for Health and Care Excellence (NICE) guidelines, Fluoxetine is the first-line selective serotonin reuptake inhibitor (SSRI) for children and adolescents under 18 years with moderate to severe depression. This recommendation is due to its proven efficacy and safety profile in this age group. On the other hand, Citalopram is not recommended as a first-line treatment in children or adolescents with depression. In fact, it carries a warning of potential dose-dependent QT interval prolongation which can lead to serious cardiac arrhythmias. Moreover, there is less evidence supporting its use in this age group compared to Fluoxetine. Paroxetine also has less supportive evidence for use in children and adolescents with depression. It has been associated with an increased risk of suicidal behaviours in young people compared to other SSRIs. Therefore, it should be used cautiously and isn't the most appropriate choice here. Sertraline, although considered safe and effective for adults with depression, lacks robust evidence for its efficacy in treating depressive symptoms in children and adolescents. Furthermore, it may have more gastrointestinal side effects compared to Fluoxetine. Lastly, Escitalopram is not typically recommended as a first-line treatment for children or adolescents either due to a lack of sufficient evidence supporting its effectiveness in this population.

Answer 7

Diarrhoea Gastrointestinal side-effects such as diarrhoea are seen in SSRI discontinuation syndrome Diarrhoea is the correct option as this young woman has stopped taking her sertraline two weeks prior to her presentation of protracted diarrhoea, which along with abdominal cramping and vomiting, are common symptoms seen in SSRI discontinuation syndrome. Furthermore, using Occam's razor, given the timeline and the normal blood results and lack of infective contacts, it is more likely to be this syndrome compared to inflammatory bowel disease or gastroenteritis. Euthymia is incorrect as the SSRI discontinuation syndrome more commonly results in increased mood change. Hypersomnia is an incorrect option because insomnia changes to the sleep pattern are more commonly seen in SSRI discontinuation. Generalised weakness is an incorrect option as this is more than likely due to diarrhoea and there is no focal neurology in the limbs to suggest anything different. Moreover, SSRI discontinuation syndrome can result in paraesthesias rather than a general feeling of fatigue and weakness. Mydriasis is an incorrect option as SSRI discontinuation syndrome is not related to these pupillary changes; in fact, the serotonin syndrome caused by taking too much SSRI can result in this. The stem also clearly states these pupils have been dilated since a young age making congenital mydriasis the most likely diagnosis in this case.