Mood stabilisers Flashcards
What disorders can be treated using mood stabilisers?
Bipolar disorders
Cyclothymia (less severe bipolar*)
Schizoaffective disorder
*very simple definition - more to it than that
What are the classes of mood stabilisers?
Lithium
Anticonvulsants
Antipsychotics
What is lithium used to treat?
What factors predict a positive response to lithium treatment?
Bipolar disorder (mainly) - also cyclothymia
Only medication to reduce suicide rate in BAD patients
Factors predicting effectiveness:
- prior long-term response by patient or by family member
- classic pure mania
- if mania happened first, and followed by depression
Before starting a patient on lithium - what investigations should be done?
U&Es - affects renal function
TSH - can cause hypothyroid
Pregnancy test - ebstein anomaly in 1st trimester*
*Can still prescribe to women of child bearing age but they should be on birth control
What monitoring must be done if a patient is started on lithium?
After 5 days, 12 hours after their last dose - check blood levels of lithium:
Goal = 0.6 - 1.2
Check lithium levels every 3 months
Check TSH & creatinine (U&Es) every 6 months
What are the side effects of lithium?
GI upset - reduced appetite, N&V, diarrhoea
Thyroid abnormalities (hence TSH checks)
Nonsignificant leukocytosis
Polyuria/polydypsia
Hair loss, acne
Reduced seizure threshold, tremor, cognitive slowing
Polyuria and polydypsia are both potential side effects of lithium
What causes this?
What serious complication involving the kidneys can arise?
Polyuria/polydypsia happen secondary to ADH (vasopressin) antagonism
Renal interstitial fibrosis can occur in a small number of patients - hence why renal function must be checked
How toxic is lithium?
What symptoms are seen at increasing levels of overdose?
Pretty darn toxic
Mild (1.5-2.0) - vomiting, diarrhoea, ataxia, dizziness, slurred speech, nystagmus
Moderate (2.0-2.5) - nausea, vomiting, anorexia, blurred vision, clonic limb movements, convulsions, delirium, syncope
Severe (>2.5) - generalised convulsions, oliguria, renal failure, death
What are the main anti-convulsants?
Valproic acid (Depakote)
Carbamezapine (Tegretol)
Lamotrigine (Lamictal)
How does Valproic acid compare to Lithium in the treatment of Bipolar disorder?
Valproic acid is as effective as lithium in prophylaxis of mania
But it is less effective in prophylaxis of depressive episodes of BAD
Valproic acid is also tolerated better than lithium
What factors predict a positive response to Valproic acid?
Rapid cycling patients* (females > males)
Comorbid substance abuse issues
Mixed patients (no idea)
Patients with comorbid anxiety disorders
*patients with frequent manic-depressive transitions
What tests must be done before starting a patient on valproic acid?
Liver function test (LFT)
Pregnancy test
FBC
What are contraindications to using Valproic acid?
Child bearing age - causes neural tube defects in pregnancy
Liver problems
How is Valproic acid monitored?
5 days for steady state so check 5/6 days after commencement - 12 hours after last dose
Goal = 50-125
Blood level not as significant as with Lithium though
What are the potential side effects of using valproic acid?
Nausea, vomiting, weight gain
Thrombocytopenia & platelet dysfunction
Sedation, tremor
Alopecia (hair loss)
What is Carbamazepine used for?
First line for acute mania and mania propylaxis
Indicated for rapid cyclers and mixed patients
Before starting a patient on Carbamazepine, what tests must be done?
LFT
FBC
ECG
How is the response to Carbemazepine monitored?
Again - 5 days to steady state
12 hours after last dose
Goal = 4-12 mcg/ml
Check level and adjust dosing after a month as it induces its own metabolism
What are the potential side effects of Carbamazepine?
Rash
Nausea, vomiting, diarrhoea
Sedation, ataxia, dizziness, confusion
AV conduction delays
Aplastic anaemia & agranulocytosis
Water retention, hyponatraemia
Drug-drug interactions
What are the benefits of Lamotrigine compared to other anti-convulsants?
Can be used in women of CBA
Can also be used for neuropathic/chronic pain
What tests must be done before commencing treatment with Lamotrigine?
LFT
How does the titration of Lamotrigine differ from that of the other anti-convulsants?
What happens if the patient stops taking Lamotrigine?
Slowly titrate dose up
Faster titration risks Steven johnson syndrome (very severe rash)
If stops for 5 or more days - then have to start at lowest dose (25mg) and titrate up again
What are the potential side effects of Lamotrigine?
Nausea & vomiting
Sedation, dizziness, ataxia, confusion
Steven Johnson’s syndrome - if any rash develops then immediately stop
Blood dyscrasias
What medications can interfere with Lamotrigine?
VPA (valproic acid) - doubles concentration so have to titrate up even more slowly
Sertraline
Case copied from presentation
33 yo woman hospitalized with her first episode of mania. She has no previous history of a depressive episode. She has no drug or ETOH history and has no medical issues.
- What medication would you like to start?
- What investigations would you do first?
- What would you discuss with the patient?
Given her first presentation was a manic episode statistically she will do better on lithium
Pregnancy test, U&Es, TSH
Discuss with her what she will use for birth control and document this discussion
Case from presentation
27 yo male is admitted secondary to a manic episode. In reviewing his history you find he has 5 to 6 manic or depressive episodes a year. He has also struggled on and off with ETOH abuse.
What medication would you start him on?
Why?
Valproic acid (Depakote)
Good for the patient because he is:
- Rapid cycler (6 episodes per year)
- comorbid substance abuse (alcohol)
You start a patient on an anticonvulsant - and check their LFTs after you have titrated to the adequate dose
Their LFTs are elevated as follows:
- ALT 48 –> 115
- AST 62 –> 140
- ALK phos 32 –> 80
Is this bad?
It is not unusual for patients on anticonvulsants to experience an increase in lfts.
As long as they do not more than triple no change in therapy is indicated
You would continue to monitor this however
