Psychiatry Medicines Flashcards
What class is chlorpromazine?
First generation (typical) antipsychotic
What class is haloperidol?
First generation (typical) antipsychotic
What class is clozapine?
Second generation (atypical) antipsychotic
What class is risperidone?
Second generation (atypical) antipsychotic
What class is olanzapine?
Second generation (atypical) antipsychotic
What class is quetiapine?
Second generation (atypical) antipsychotic
When might you consider using clozapine?
Treatment-resistant psychosis.
Only after two other antipsychotics (including at least one non-clozapine atypical antipsychotic) have been trialled at full dose and not been effective.
What are the important adverse reactions associated with antipsychotics?
Weight gain due to ↑ appetite
D2 blockade:* (Extrapyramidal side effects) - Acute dystonia - Akathisia - Parkinsonism - Tardive dyskinesia - Gynaecomastia - Galactorrhoea
Cholinergic blockade:
- Dry mouth
- Blurred vision
- Impotence
- Constipation
- Urinary retention
Neuroleptic malignant syndrome (fever, tremor, rigidity, autonomic instability, delirium)
Cardiac arrhythmias (prolonged QTc leading to potentially fatal arrhythmias)
Hypersensitivity reactions:
- Blood dyscrasias (neutropenia with clozapine)
- Cholestatic jaundice
- Photosensitive dermatitis
Occular complications:
- Corneal and lens opacities
(Can all be associated with antipsychotics but those marked with * are less severe with clozapine, quetiapine and olanzapine - all second-generation (atypical) antipsychotics. Thought to be due to their strong 5-HT blocking effect and relatively weak D2 blockade)
A 60-year-old man with a long-standing diagnosis of schizophrenia presents to the emergency department with recent-onset delirium.
He has hyperthermia, tachycardia of 140 bpm, and generalised muscle rigidity. His medication has been recently changed. Investigations for possible causes, including sepsis, are all normal. He has mild elevation in WBC and elevated serum creatine kinase levels (1200 units/L).
What should you do?
The patient is likely to be taking antipsychotic medication for their schizophrenia. The history and clinical findings (delirium, rigidity, autonomic instability) are consistent with neuroleptic malignant syndrome - a known and serious adverse effect of antipsychotic medication.
Their antipsychotic medication must be stopped immediately and they should be admitted for supportive therapy. You should consider whether they require stepping up to ICU.
A patient has recently been started on an antipsychotic following a diagnosis of schizophrenia. They return to you complaining of muscle twitches. Which of the following is the most likely drug they are taking?
A) Clozapine
B) Haloperidol
C) Olanzapine
D) Risperidone
B) Haloperidol
Acute dystonic reactions (such as muscle spasms and parkinsonian movements) are examples of extrapyramidal side effects that are more commonly caused by typical (1st generation) antipsychotics, such as haloperidol.
The other answers are all atypical (2nd generation) antipsychotics. While they can lead to EPSE’s, these are less common. They are more likely to cause metabolic side-effects: weight-gain, diabetes, dyslipidaemia.
A young woman who is planning to get pregnant is currently taking paroxetine and wants to know if it will have any adverse effects during pregnancy. What should you advise her?
It is advised that paroxetine should be avoided during pregnancy unless the benefits outweigh the risk, as paroxetine can lead to a small increased risk of congenital malformations.
Paroxetine is an SSRI. SSRI’s carry increased risks if taken during pregnancy:
- First trimester: congenital heart defects
- Third trimester: persistent pulmonary hypertension
- Paroxetine has an increased risk of congenital malformations, particularly in the first trimester
A 35-year old patient presents with a one week history of strange behaviour: walking around the house at night, talking to people who aren’t there. During the consultation the patient seems distracted and occasionally smiles and waves at the wall behind you. She does not seem distressed and politely asks if she can leave.
The patient usually take loratadine 10mg od for hay-fever, salbutamol and beclometasone inhalers for asthma and has recently started the a combined oral contraceptive for contraception. She is also taking a course of prednisolone following a recent exacerbation of her asthma.
Which of the following is most likely to be the cause of her symptoms?
A) Beclometasone inhaler B) Combined oral contraceptive pill C) Loratadine D) Prednisolone E) Salbutamol inhaler
D) Prednisolone
Sudden onset psychosis following course of corticosteroids – consider steroid-induced psychosis.
Steroid-induced psychosis is a recognised side effect of corticosteroid use. In this scenario, both her beclometasone inhaler and prednisolone are corticosteroids, however prednisolone would certainly be a higher dose than beclometasone and would therefore be the most likely cause of her symptoms.
