WK 27 - Bipolar affective disorder in practice Flashcards
What is bipolar affective disorder?
Abnormally elevated mood or irritability alternates w/ depressed mood
What is included in a physical check of someone w/ bipolar disorder?
Annually:
- Weight or BMI
- Diet
- Nutritional status + level of activity
- CV status (pulse + BP)
- Metabolic status (fasting blood glucose, prolactin, lipid + liver function)
- Lithium (renal, TFT + calcium)
What happens when a person is suspected bipolar disorder?
Refer to specialist mental health service team
Give examples of acute relapses
- Mania
- Depression
- Rapid cycling
Outline the treatment for acute hypomania
- Asses patient
- W/draw antidepressants/stims
- Initiate: haloperidol, olanzapine, quetiapine or risperidone
- Poor toleration at max dose = add lithium or valproate
- Already taking lithium: check plasma levels + add antipsychotics
- ST: benzo (agitation)
- Psychotherapy
What agents are not recommended for mania?
- Antidepressants (induce mania)
- Lamotrigine (bipolar depression)
- Gabapentin + topiramate
- Carbamazepine + antipsychotics metabolized by CYP3A4 (interaction)
Outline the treatment of bipolar depression
- Psychological interventions
- Antidepressant monotherapy = not recommended
- Fluoxetine + olanzapine then atypical - no response then lamotrigine
- Tricyclic + venlafaxine avoided
Outline the long term management of bipolar disorder
Prophylaxis indicated:
- 2/more acute episodes bipolar I
- 1st line: lithium, valproate or olanzapine
- 2nd line: lamotrigine or carbamazepine
- Continue for 2 yrs
Outline the use of lithium when treating bipolar disorder
- Prescribed by brand + name
- 6 month trial
- For: acute mania, prophylactic for mania + depression
- 1st line: long term to treat relapse
What is needed monitoring every 6 months during lithium treatment?
- Serum electrolytes
- eGFR
- Body-weight/BMI
- Lipids
- Thyroid function
- Calcium levels
- FBC (initiation) + ECG if cardiac risk factors
Outline the drug monitoring of lithium
- Every 3-6 months
- Initially weekly
- Additional tests if concerns
- Every 5-7 days after dose change
What is considered toxic lithium levels?
> 1.5mmol/L
Outline the side effects of lithium
- Fine tremor
- Sedation
- QT prolongation
- Polyuria, polydipsia
What are the long term side effects of lithium?
- Weight change
- Thyroid disorder
- Hyperparathyroidism
- Renal impairment
What are signs of lithium toxicity?
> 1.5mmol/L:
- Lack of appetite
- Blurred vision
- Slurred speech
> 2mmol/L:
- Muscle twitch
- Convulsion
- Unconsciousness
Outline the interactions of lithium
Anything that impacts renal + sodium levels:
- Diuretics
- NSAIDs
- ACE inhibitors
- Antidepressants
Others:
- Carbamazepine
- Haloperidol
Outline some patient advice when giving lithium
- Carry card all times
- Same brand
- Tell before buying OTC
- Adequate fluid
- Avoid changes to diet that affect sodium
- Regular blood tests
- Reliable contraception
- S/e: dry mouth, metallic, weight gain
- Recognise toxicity: blurred vision, slurred words, confusion
What are pharmacist points to remember when giving lithium?
- Give at night
- If twice daily dose. - morning dose taken after lithium level check
- If admitted to hospital on lithium, check blood
- Lithium book up to date
What is valproate prescribed for?
- Acute mania
- Prophylactic agent
What are the different forms of valproate?
- Sodium valproate
- Valproic acid
- Semi-sodium valproate
- Semi-sodium + sodium val = metabolised to valproic acid
What are the side effects of valproate?
- Weight gain
- GI irritation
- Impaired liver function
- Risk of suicidal thoughts
- Teratogenic
When initiating valproate, what needs to be measured?
- Weight/BMI
- FBC
- Liver function test
What are the interactions of valproate?
- Less strongly protein bound drugs (warfarin) displace valproate = higher free levels = toxicity
- Drugs that inhibit cytochrome P450 enzymes inc valproate
What are atypical antipsychotics used for?
Acute mania
What are the long term side effects of atypical antipsychotics?
- Weight gain
- Dyslipidemia
- Hyperprolactinaemia
- HT
- Red seizure threshold
- QT interval prolongation
- VTE
What is lamotrigine indicated for?
Prevention of depressive disorder in bipolar I - not acute manic or depressive episode
What are the side effects of lamotrigine?
- Skin rashes
- Headache, nausea
- Blood disorder
- Risk of suicidal thoughts
What are the interactions of lamotrigine?
- Plasma conc red by: phenytoin, primidone, carb, oestrogen + progestogen
- Plasma conc inc: valproate
