7 - Psychiatric Drugs (Antidepressants and Mood Stabilisers) Flashcards
What are the side effects of clozapine?
- Constipation - fatal
- Sedation
- Hypersalivation
- Changes in BP
- Tachycardia – usually benign but could be cardiomyopathy so ECG
- Weight gain
- Seizures
- Urinary incontinence
What is paliperidone and how is it started?
- Depot version of Risperidone
- Does not require oral medication (Risperidone) to be taken during initiation, so is a good choice in a patient who is currently refusing all oral medications
- Loading doses of IM injections (Day 1 and Day 8 of treatment, then monthly thereafter)
- If a patient remains stable for at least four months on monthly dose can be given 3 monthly dose
What is a CTO?
Community Treatment Order
This can be used to specify conditions to which the patient is subject to on discharge, and the patient may be recalled to hospital if the conditions are not met, even if not under MHA
Means clinicians needn’t wait for the patient to relapse and become risky before re-admitting them to hospital, thus avoiding relapses and possible consequences of relapses
Sangita is a 27 year old woman who presents with her first episode of psychosis. She is extremely worried about gaining weight and does not want to take any medication if it causes weight gain.
What would be an appropriate antipsychotic?
Aripiprazole as this is the only weight neutral choice
- A 47 year old man is admitted to hospital with a diagnosis of a Delusional Disorder. He has a significant cardiac history.
Which would be the safest antipsychotic to prescribe?
a. Aripiprazole
b. Chlorpromazine
c. Haloperidol
d. Sulpiride
e. Zuclopenthixol
Answer : A the others all cause QTc prolongation.
Which of the following SSRI’s is only recommended in reduced doses in the elderly?
a.) Citalopram b.) Fluoxetine c.) Fluvoxamine d.) Paroxetine e.) Sertraline
A
Citalopram in higher doses is thought to prolong the QT interval which could lead to cardiac arrhythmia’s
Which of the following drugs should not be routinely prescribed for a patient on Lithium?
a. ) Aspirin
b. ) Codeine Phosphate
c. ) Gabapentin
d. ) Paracetamol
e. ) Tramadol
A
Aspirin is an NSAID. NSAID’s may increase the concentration of lithium.
- Which of the following is not a recommended treatment for mania?
a. ) Lamotrigine
b. ) Lithium
c. ) Olanzapine
d. ) Quetiapine
e. ) Sodium Valproate
A
Lamotrigine can be used to treat bipolar depression. The remaining treatments are all recommended for the treatment of mania
- Stevens Johnson Syndrome is a rare side effect of which of the following?
a. ) Lamotrigine
b. ) Lithium
c. ) Lorazepam
d. ) Paroxetine
e. ) Sodium Valproate
A
Stevens-Johnson syndrome & toxic epidermal necrolysis are rare side effects with Lamotrigine, which can be used sometimes for treatment resistant depression
Patients are advised to see their doctor immediately if they develop a rash.
How long do people ideally need to stay on antidepressants before they are weaned off?
Depression: 6 months (12 in elderly)
Anxiety: 12 months
Recurrent Depression: 2 years
What route are antidepressants given and how long do they take to work?
PO
Takes 2 weeks minimum but can take up to 6 weeks to feel effect
Can have Mirtazapine Bucally and Selegeline (MAOi) transdermally but rare
Give 3 examples of an SSRI and indications for this drug.
Examples: Sertraline, Citalopram, Fluoxetine, Escitalopram
Indications: First line antidepressant, Panic attacks, Anxiety, OCD, Eating disorders, Hot flushes in menopause
Sertraline is best for depression in IHD
What are some contraindications to SSRIs?
Absolute
- Mania in bipolar
- Poorly controlled epilepsy
- MAOI use in last 2 weeks
- Long QT (Citalopram)
- Severe hepatic impairment
Relative
- Early pregnancy (congenital heart defects)
- Hyponatraemia in elderly
- Bleeding disorders
What are the risks of using SSRIs in the third trimester of pregnancy?
- Peristent pulmonary hypertension of baby
- Neonatal withdrawal symptoms
What are the side effects of SSRIs?
Initial
- Increase in anxiety/depression
- Suicidal thoughts
Long-term
- Dry mouth
- Weight changes
- Insomnia
- Nausea and Vomiting/GI upset
- Sexual dysfunction
- Palpitations
- Drowsy
- Shaky
- Constipation/Diarrhoea
- Anorgasmia, ED, Reduced libido that can persist after cessation
- Hyponatraemia
- Gastric ulcer
- Long QT (Citalopram)
What are some side effects for the SSRI Citalopram?
What are some drug interactions with SSRIs?
- Anti-epileptics: reduces seizure threshold
- Aspirin/NSAIDs/Antiplatelets: increased risk of bleeding
- Carbamazepine: lower level of Sertraline
- Grapefruit juice: higher level of Sertraline
- Lithium: concurrent use Serotonin syndrome and Long QT
- MAOI: high risk of NMS and SS, CI
Which SSRIs have a risk of QT prolongation and Torsades De Pointes?
- Citalopram
- Escitalopram
What monitoring needs to be done on SSRIs?
None
Follow up in first 1-2 weeks then weekly for 4 weeks due to suicide risk on starting
Do ECG before starting Citalopram/Escitalopram
How may SSRI toxicity present?
Very hard to OD, few symptoms and unlikely to cause coma
Symptoms: tremor, tachycardia, vomiting
Screen for symptoms of Serotonin syndrome
May cause wide complex bradycardia and torsade de pointes if Citalopram or Escitalopram so do ECG
Why are SSRIs usually preferred over TCA?
Have the same efficacy
- Better tolerated side effects
- Safer in overdose
- Less sedating
- Less cardiovascular side effects
TCAs are second-line treatments for depression.
What is the mechanism of action of TCAs? Give 3 examples of a TCA and indications for this drug.
Block the re-uptake of both serotonin and noradrenaline
Examples
Sedative: amitriptyline, clomipramine
Less Sedative: lofepramine, and nortriptyline.
Indications
- Depression (not Amitriptylline as high toxicity)
- Neuropathic pain
- OCD
- PTSD
- GAD (better to use sedative ones)
- Nocturnal enuresis
What are the contraindications for TCAs?
- Arrhythmias (Long QT)
- Heart block
- Severe hepatic impairment
- During the manic phase of bipolar disorder
- In the immediate recovery period after myocardial infarction
- Taking a monoamine oxidase inhibitor (MAOI)
- Enlarged prostate
What are some side effects with tricyclic antidepressants?
- Anticholinergic syndrome: Urinary retention, Blurred vision, Constipation, Dry mouth
- Drowsiness
- Orthostatic hypertension
- Palpitations
- Long QT syndrome
What patient group needs to be careful with TCAs?
Elderly: Prone to more side effects so cardiac monitoring, Use half doses
Depression: Avoid Amitriptylline and Dosulepin as high toxicity risk
What monitoring needs to be done whilst on TCAs?
- Suicide risk in first 1-2 weeks so follow up weekly for first 4 week
- ECG: Annually if on high doses or if taking other QT prolonging drugs as well
What is the toxicity like with TCAs and what are the side effects with toxicity?
Narrow Therapeutic Index (easy to OD)
SE: Arrhythmias and reduced cardiac contractility, CNS depression and seizures
Need sodium bicarbonate treatment to alkalise blood
What are some drug interactions with TCAs?
- Lithium — Serotonin syndrome, or NMS In addition. QT prolongation or torsades de pointes
- Monoamine oxidase inhibitors (MAOIs) — concurrent use is contraindicated
- Other sedative drugs (alcohol, barbiturates, benzodiazepines) — TCAs are sedating and co-administration with other sedating drugs may have a synergistic effect.
- Phenylephrine — blood pressure effects of phenylephrine may be increased by TCAs, leading to increased risk of arrhythmias
What over the counter medication should you avoid with antidepressants?
St John’s Wort
It is an enzyme inducer so decreases amount of antidepressant. If patient stopped taking this whilst on anti-depressants could lead to toxicity
What are some examples of SNRIs and what are some indications for this?
Examples: Venlafaxine, Duloxetine
Indications: Severe depression, ADHD, Neuropathic pains
What are some contraindications for SNRIs?
- High risk of cardiac arrhythmia
- Uncontrolled hypertension
- Glaucoma
- Epilepsy
- Hepatic impairment (duloxetine)
- Severe renal impairment <30ml/min (duloxetine)
What are some side effects of SNRIs (Venlaxafine and Duloxetine)?
- Nausea
- Headaches
- Sweating
- Dry mouth
- Constipation
- Blood pressure increases, flushing
- Blurred vision
- Cholesterol level increases
- Decreased appetite/Weight loss
- Sexual dysfunction
- Sedation
- Hyponatraemia (SIADH)
What antidepressants are favoured in severe depression?
- TCAs
- Venlaxafine
What antidepressants have an increased risk of PPH in pregnant women?
SSRI and SNRI if used a month before birth