Lithium Flashcards
(17 cards)
Why should lithium always be prescribed by brand name?
Because lithium preparations vary widely in bioavailability, and prescribing by brand reduces the risk of toxicity or subtherapeutic dosing.
Is lithium citrate dose-equivalent to lithium carbonate?
No, they are not dose-equivalent.
Name 3 absolute contraindications to lithium use.
Cardiac rhythm disorders, significant renal impairment, untreated hypothyroidism.
When should lithium be prescribed with caution?
In elderly patients, those on diuretics, with epilepsy, myasthenia gravis, psoriasis, or QT prolongation.
Name a situation where lithium dose should be reviewed.
During vomiting, diarrhoea, infection with sweating, or post-surgery.
What are common initial side effects of lithium therapy?
Nausea, diarrhoea, muscle weakness, vertigo, dazed feeling.
Name three long-term adverse effects of lithium.
Hypothyroidism, hyperparathyroidism, nephrotoxicity.
Can lithium cause renal tumours?
Rarely, in long-term use, it has been associated with renal microcysts and tumours in those with severe renal impairment.
When should lithium levels be measured?
1 week after starting or dose change, then weekly until stable, then every 3 months.
How long after dosing should lithium levels be taken?
12 hours post-dose.
What blood tests should be done every 6 months on lithium?
U&Es, eGFR, calcium, thyroid function, weight/BMI.
Name two drug classes that increase lithium levels.
Diuretics (especially thiazides) and NSAIDs.
What can happen with lithium + ACE inhibitors?
Increased lithium levels and risk of renal failure.
What antidepressants may interact with lithium?
SSRIs, TCAs, venlafaxine, duloxetine — possible CNS toxicity.
What are early signs of lithium toxicity?
Nausea, diarrhoea, tremor, muscle weakness, lethargy, blurred vision.
At what level does lithium toxicity usually occur?
At serum levels ≥1.5 mmol/L; severe toxicity ≥2 mmol/L.
What should women of childbearing age be told?
Use effective contraception due to potential birth defect risks.
