Lithium Flashcards
(15 cards)
Lithium indications
After trying antipsychotics and they haven’t worked:
- Treatment and prophylaxis of mania
- treatment and prophylaxis of bipolar disorder
- treatment and prophylaxis of recurrent depression
- treatment and prophylaxis of aggressive or self harming behaviour
What are the contraindications?
Sodium hates lithium so anything affecting sodium balance or kidneys is a big no no!
- dehydration
- low sodium diets (increases lithium concentration)
- Untreated hypothyroidism (lithium affects T4 production and can cause hypothyroidism
- Cardiac disease
- addisons disease
Lithium Cautions
- avoid abrupt withdrawal
- diuretic treatment will increase toxicity
- QT interval prolongation
- Review the doses in (diarrhoea,elderly,vomitting,surgery,intercurrent infections)
- long term use has been associated with thyroid disorders and mild cognitive and memory impairment
- for long term treatment, monitor thyroid function every 6 months
- assess need for continuous therapy regularly and maintain patients after 3-5 years on lithium only if benefits persist
Side effects of lithium
- Gi disturbance (n and v)
- CNS (drowsiness,confusion and unsteadiness)
- electrolyte imbalance
- hyperglycaemia
- hypothyroidism (weight gain,fatigue and hair loss)
- Cardiomyopathy and AV block
- seizures ( caution with epileptics)
- tremor, movement disorders,muscle weakness
- leukocytosis
- renal dysfunction(polydipsia - excessive thirst, polyuria)
- memory loss
- skin reactions and skin ulcers
- vision disorders (blurred vision)
- intracranial hypertension(persistent headache and visual disturbance)
- QT interval prolongation
Lithium Mnemonic
Levels
Increased urination
Thirst,tremors and teratogenic
Hypothyroidism (weight gain and fatigue)
Interactions(NSAIDS,ACE,ARB,DIURETICS,ANTACIDS)
Upset stomach (d,n,v)
Muscle weakness
Skin reactions( acne and psoriasis)
Signs of lithium overdose
- increasing GI disturbances (n.v)
- visual disturbance
- polyuria,muscle weakness
- fine tremor increasing to coarse tremors
- CNS disturbances (confusion, drowsiness,lack of coordination and restlessness)
- cardiac arrhythmias
- hyernatraemia
- AV block
- renal failure
- seizures
- Coma and sudden death
Lithium - pregnancy and breastfeeding
Avoid in breastfeeding - present in milk and risk of toxicity in infants
Pregnancy:
- avoid if possible especially in 1st trimester (risk of teratogenicity,including cardiac abnormalities)
- dose requirements increase during 2nd and 3rd trimerser(but on delivery return abruptly to normal)
- monitor serum concentration closely during pregnancy (risk of toxicity in neonates)
- effective contraception should be used during treatment with females of child bearing age.
Monitoring requirement
- Narrow therapeutic index
- Take blood sample 12hrs after dose to achieve a serum concentration of 0-1 mmol/L (lower end of the range for maintenance and elderly patients)
- 0.8-1mmol/l (for acute episodes of mania and patients who previously relapsed)
- routine serum lithium concentration monitoring should be performed weekly after initatiation and after each dose change until stable, then monitor every 3 months for the first year and every 6 months thereafter
What do we monitor with patients on lithium
Before initiation:
- cardiac,thyroid and renal function
- ECG,BMI/Body weight, wbc count and serum electrolytes
During treatment (every 6 months):
- BMI or body weight
- serum electrolytes
- eGFR
-Thyroid function
How do you discontinue lithium - Treatment cessation
- abrupt discontinuing increases the risk of relapse
- Reduce gradually over a period of time for at least 4 weeks (up to 3 months preferred)
- warn patients/carers about risk of relapse if stopped abruptly
- if lithium is stopped or discontinued abruptly, consider changing therapy to an atypical antipsychotic or valproate
Patient and carer advice
- Advise pts to report signs of toxicity
- hypothyroidism weight gain
-renal dysfunction - including polyuria and polydipsia - benign intracranial hypertension - persistent headaches and visual disturbances
- maintain adequate fluid intake
- avoid dietary changes which reduce or increase sodium intake
- give patients a lithium treatment pack(info booklet about lithium, lithium alert card and record and book tracking lithium conc)
- Maintain same brand - comes as lithium citrate and carbonate - different brands = different bioavailability
- hyponatraemia predisposes to lithium toxicity so avoid dehydration or anything that changes sodium levels
What increases lithium conc - INTERACTIONS
The following INCREASE the conc of lithium:
ACE inhibitors and arbs
Diuretics (loop and thiazide)
NSAIDs
Metronidazole
Tetracycline
DECREASE the conc of lithium
- sodium contains antacids and soluable/effervescent analgesics (high salt)
- urinary alkalising agents for cystitis
Theophylline - osmotic and carbonic anhydrase inhibitor diuretics
Neurotoxicity with lithium
- carbamazepines
- antipsychotics eg. Quite. And Risperidone
- SSRI
- Triptans
-Calcium Chanel blockers eg,Verapamil
WHICH increase the risk of serotonin syndrome with lithium
SSRIs eg. Citalopram
MAOIs
Tramadol
St John’s wort
Sumatriptan
