1.3.4 Adverse Effects Flashcards
A patient presents to you on the ward with a ‘muscle spasm’ on his neck. He was started on 5mg Haloperidol (bd) few days ago. What is the most likely problem?
- Acute dystonia
- Akathisia
- Neuroleptic malignant syndrome
- Parkinsonism
- Tardive dyskinesia
An acute dystonic reaction consists of sustained, often painful muscular spasms, producing twisting abnormal postures.
50% occur within 48 hours of administering an antipsychotic for the first time.
Which of the following is the most common adverse effect of valproate?
- Ataxia
- Diarrhoea
- Hair loss
- Persistent elevation of hepatic transaminases
- Reversible thrombocytopenia
Diarrhoea.
Nausea, vomitting, dyspepsia and diarrhea are the most common adverse effects of valproate.
In managing the hypertensive crisis associated with monoamine oxidase (MAO) inhibitors and the ingestion of food with tyramine, the agent of choice is:
- Carvedilol
- Chlorpromazine
- Phentolamine
- Propranolol
- Reserpine
Phentolamine = reversible nonselective alpha adrenergic antagonist.
Hypertensive crisis during MAOI use can be managed using:
- Phentolamine or
- Phenoxybenzamine.
Phenoxybenzamine - irreversible nonselective alpha adrenergic antagonist.
A 36-year-old woman with schizoaffective disorder, living at a psychiatric rehabilitation unit is admitted to a medical ward for treatment of a suspected intestinal infection resulting in dehydration, vomiting and fever. Her psychiatric condition has been managed with a stable dose of clozapine for the last 9 months. At the medical ward, she appears confused with reduced orientation to time and appears lethargic. She also has stiffness and some rigidity in movements. The most appropriate recommendation at this stage would be to
- Add a benzodiazepine
- Add an anti epileptic
- Add Benztropine
- Discontinue clozapine
- Switch to a typical antipsychotic
Discontinue clozapine
Atypical NMS can present in this manner.
Benzatropine is an anticholinergic drug used in patients to reduce the side effects of antipsychotic treatment, such as parkinsonism and dystonia.
Benzatropine is also a second-line drug for the treatment of Parkinson’s disease. It improves tremor, but not rigidity and bradykinesia. Benzatropine is also sometimes used for the treatment of dystonia, a rare disorder that causes abnormal muscle contraction, resulting in twisting postures of limbs, trunk, or face.
A trainee doctor working at a medical ward asks your advice whilst on call. She is requesting an assessment for an agitated and hallucinating inpatient on the medical ward. She reports that he appears flushed with a hot and dry skin, mydriasis, rapid pulse and diminished bowel sounds. Which of the following is the best suggestion for you to make at this stage?
- Administer atropine
- Discontinue anticholinergic drugs
- Prescribe diazepam
- Prescribe haloperidol.
- Prescribe IM olanzapine
Discontinue anticholinergic drugs.
Anticholinergic delirium constitutes a medical emergency.
Symptoms of anti- cholinergic delirium include:
- hot, dry skin;
- dry mucous membranes;
- dilated pupils;
- absent bowel sounds; and
- tachycardia.
Physicians must first determine and remove the offending agent because patients are at a high risk for cholinergic crisis.
Atropine can be used to treat anticholinergic delirium symptoms once the agent has been removed.
Which of the following is true with regard to the side effects of escitalopram when compared to citalopram?
- Escitalopram and citalopram have similar side-effect profiles
- Escitalopram is associated with fewer sexual side effects
- Escitalopram is associated with greater cardiovascular effects
- Escitalopram is associated with greater gastrointestinal effects.
- Escitalopram is associated with greater weight gain.
Escitalopram and citalopram have similar side-effect profiles.
Citalopram is a racemate consisting of a 1:1 mixture of the R(–)- and S(+)-enantiomers.
Non-clinical studies show that the serotonin reuptake inhibitory activity of citalopram is attributable to the S-enantiomer, escitalopram.
Escitalopram is the active S- isomer of the antidepressant citalopram.
It is claimed that Escitalopram has more efficacy and a faster onset of effect than citalopram.
The side effect profile of escitalopram is similar to that of other SSRIs
The principal cause of death following tricyclic antidepressant (TCA) overdose is
- Cardiac arrhythmia.
- cerebral oedema
- malignant hypertension
- respiratory failure
- seizures
Cardiac arrhythmia.
A membrane stabilizing effect can precipitate dysrhythmias and altered myocardial conduction.
This activity occurs from blockade of inward/fast sodium channels, resulting in altered repolarization and conduction.
This effect occurs distal to the AV node, producing a depression of the His-Purkinjie conduction system and a direct negative inotropic effect.
Intravenous sodium bicarbonate is the preferred pharmacologic treatment of choice to reverse TCA-induced cardiac conduction defects.
This is the commonest cause of death in an overdose with TCAs.
Which of the following drugs is contraindicated for a patient receiving a monoamine oxidase (MAO) inhibitor?
- Atropine
- Budesonide
- Chlorpromazine
- Meperidine
- Trifluoperazine
Meperidine is an opioid that can interact with monoamine oxidase inhibitors resulting in serotonin syndrome.
A 34 year old man is being treated with Carbamazepine and Levothyroxine for a rapid cycling bipolar disorder. As his illness was poorly controlled, Clozapine was added after which his condition has stabilized. The patient’s most recent white blood cell count is below 3,000/cu mm. The most appropriate immediate intervention is
- decrease the dose of clozapine
- decrease the dose of carbamazepine
- discontinue the carbamazepine
- discontinue the clozapine.
- discontinue the thyroxine
discontinue the clozapine.
If there is a red alert (WCC
Which of the following is an important difference between NMS and serotonin syndrome clinically?
- CPK elevation in serotonin syndrome
- Hyperreflexia in serotonin syndrome
- Hypomanic presentation in NMS
- Presence of myoclonus in NMS
- Subacute onset in serotonin syndrome
Hyperreflexia in serotonin syndrome.
Symptoms such as hyperreflexia and myoclonus are attributed to the enhanced release of serotonin in serotonin syndrome and are not seen in NMS.
Priapism is a dreaded side effect associated with
- Clomipramine
- Fluoxetine
- Imipramine
- Phenelzine
- Trazodone
Trazodone has been associated with priapism in rare cases; this must be treated urgently to avoid long-term impairment.
Priapism = persistent and often painful erection.
Which antidepressant is contraindicated in closed angle glaucoma?
- Bupropion
- Buspirone
- Mirtazapine
- Paroxetine
- Sertraline
Paroxetine.
Anticholinergic side effects include dry mouth, constipation, urinary retention, blurred vision, and less commonly narrow-angle glaucoma.
These effects are usually dose-related and worse in patients with pre-existing defects.
Paroxetine has significant anticholinergic properties
The cardiotoxic effects of tricyclic antidepressants would include all of the following except
- Arrhythmias
- Atrioventricular Block
- QT Prolongation
- Reduction in cardiac output
- ST elevation or depression
Reduction in cardiac output.
TCAs affect cardiac conduction; as a result, they have antiarrhythmic properties and can slow cardiac conduction.
These effects are responsible for the cardiotoxicity of TCAs and their danger in overdose.
TCAs do not affect cardiac output, however they should not be used in patients with a preexisting conduction delay greater than a first-degree block or in patients immediately after myocardial infarction.
A specific side effect of Mianserin that requires regular monitoring is
- anticholinergic activity
- Bone marrow suppression
- cardiotoxicity
- QT prolongation
- Risk of serotonin syndrome
Bone marrow suppression.
Mianserin was the first of the second-generation antidepressants to be developed.
It lacked the amine reuptake inhibitory and MAOI actions of the first-generation drugs and also lacked the cardiotoxicity and anticholinergic activity of the TCAs.
However, it was sedative (antihistaminic), caused postural hypotension (alpha-1 blockade) and also caused blood dyscrasias and agranulocytosis in a small number of patients. This has limited the use of mianserin in recent years.
Which one among the following is a common side effect of MAOIs
- Bone marrow suppression
- Cardiac arrhythmias
- Hepatocellular jaundice
- Peripheral neuropathy
- Postural hypotension
Postural hypotension.
Common side effects of MAOIs would include insomnia, postural hypotension, peripheral oedema, restlessness, nausea, dizziness, sexual difficulties, sweating and tremor.
Rare side effects would include hepatocellular jaundice, Peripheral neuropathy, bone marrow suppression, and cardiac arrhythmias .
Cheese Reaction is one of the most common and dangerous side-effects of
- Atypical Antipsychotics
- MAOIs
- SNRIs
- SSRIs
- TCAs
MAOIs.
The gut MAO-A generally breaks down the tyramine in the diet. If tyramine enters the circulation in large amounts, this results in a release of noradrenalin from endogenous storage sites, causing a sudden and fatal rise in blood pressure. This can take place when an individual taking MAO-A inhibitors (that reduces the activity of gut MAO) ingests large quantities of foods containing tyramine.
Agranulocytosis as a side effect of Clozapine occurs most commonly during the
- First 18 weeks of treatment
- First 28 weeks of treatment
- First 48 weeks of treatment
- First 8 days of treatment
- First 8 weeks of treatment
80% of the cases develop during the first 18 weeks of treatment but may occur at any time.
