Lithium Flashcards
What is lithium used for?
Treatment and prevention of:
- Mania
- Bipolar disorder
- Recurrent depression
- Aggressive or self-harming behaviour
What are some contra-indications with Lithium?
- Dehydration
- Low sodium diets (increase in lithium conc)
- Untreated hypothyroidism
- Cardiac disease
- Addison’s disease
What are some cautions of of Lithium?
- Abrupt withdrawals
- Diuretic treatment as it can increase the risk of toxicity.
- QT interval prolongation
- Long term use can cause Thyroid disorders & mild cognitive and memory impairment. SO monitor thyroid function every 6 months
In what cases must the dose of Lithium be reviewed?
- Diarrhoea
- Elderly
- Vomiting
- Surgery & intercurrent infection
What are some of the side effects of Lithium?
- Hypothyroidism (weight gain, fatigue, hair loss)
- Seizure (caution with epileptics)
- Tremor, movement disorders, movement weakness.
- QT interval prolongation
- Renal dysfunction (polydipsia - excessive thirst, polyuria)
- Upset stomach (diarrhoea, nausea, vomiting, etc)
- CNS (confusion, visual disturbances, fine tremors)
- Electrolyte imbalance
- Hyperglycaemia
- Skin reactions/skin ulcers
What are the signs of lithium overdose?
- Hypernatremia
- CNS disturbance (confusion, drowsiness, lack of concentration, restlessness)
- Increasing G.I disturbances (N&V)
- Visual disturbances
- Polyuria
- Renal failure
What are the interactions of Lithium?
- NSAIDS
- Acel
- ARBs
- Diuretics
- Antacids
Can Lithium be used when breastfeeding?
No, as it is present in milk and risk of toxicity in infants
Can Lithium be used when pregnant? And what are the rules regarding pregnancy and Lithium?
Yes but avoid
Esp avoid in 1st trimester (risk of teratogenicity, including cardiac abnormalities)
If used in 2nd & 3rd trimester, dose requirements increase.
On delivery, return abruptly to normal dose.
Monitor serum concentration closely during pregnancy
What is the therapeutic range for lithium? And when are samples taken?
Lithium is a narrow therapeutic drug.
0.4 - 1mmol/L - for maintenance & elderly patients
0.8 - 1mmol/L - for acute episodes of mania & patients who previously relapsed)
Blood samples taken 12 hours after dose to achieve a serum concentration of 0.4-1.
What monitoring must be done for Lithium?
Routine serum-lithium conc should be done weekly after initiation and after each dose change until stable, then every 3 months for the first year, then every 6 months.
Before treatment:
- Cardiac, thyroid & renal function
- ECG, BMI/body weight, FBC & serum electrolytes
During:
- BMI or body weight
- Serum electrolytes
- eGFR
- Thyroid function
What must be monitored every 6 months with Lithium?
- BMI
- Electrolyte
- Thyroid function
- Renal
How must lithium be discontinued?
Reduce gradually over a period of at least 4 weeks (up to 3months preferred)
What’s an alternative for Lithium?
Atypical antipsychotic & Valproate
What patient & carer advice must be given for Lithium?
- Advice of risk of relapse if stopped abruptly.
- Report signs & symptoms of lithium toxicity
- Maintain adequate fluid intake.
- Avoid dietary changes which reduce or increase sodium intake.
- Renal dysfunction including polyuria & polydipsia.
- Advice on hyperthyroidism (weight gain)
- Benign intracranial hypertension (persistent headache & visual disturbances)
- Read lithium treatment pack (info booklet, alert card, record book for serum conc)
