Lithium is a mood stabilising drug used in the following situations 

• Prevention and treatment of mania 

• Prevention of bipolar disorder (manic depressive disorder) : decreasing the no: and severity of relapses. or effective in preventing MANIC relapses compared to DEPRESSIVE relapses 

• Combination therapy

• Prevention of recurrent depression 

• Augmentation thearpy in treatment resistant depression 

 

​Lithium is a drug with a narrow therapeutic window 

Target levels 0.4 -  1.0 mmol/l

Exists as lithium carbonate and lithium citrate 

Up to 1.2mmol/l in acute manic episodes

Overdose:  > 1.5mmol/l may be fatal

Following release from formulation, lithium is rapidly & completely absorbed.

Treatment and prophylaxis of bipolar disorder (manic depressive disorder)

 

The effects of lithium prophylaxis may not be exerted for 6-12 months post therapy initiation. 

 

 

Chronic use of lithium: 

Is associated with thyroid disorders and mild cognitive and memory impairment 

Should be undertaken with careful risk and benefit assessments 

Requires thyroid function monitoring every 6 months (should be more regularly monitored if thyroid function deteriorates) 

 

 

Monitoring 

Click here to see what monitoring is required for lithium and other drugs used in bipolar 

 

 

Adverse effects 

• Adverse effects are usually dose dependant, these include:

• Gastrointestinal disturbances, 

• Polyuria (occurs with twice a day dosing)

• Polydypsia 

• Psoriasis and acne may be worsened by the use of lithium 

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Interactions of lithium with: 

 

• Diuretics:  Frequent use  (especially thiazide diuretics) is hazardous and must be avoided as lithium toxicity is worsened by decreased sodium levels 

• ACE inhibitors: decrease lithium excretion causing increased lithium concentration 

• Analgesics:   e.g. NSAIDs also reduce lithium excretion which increases the risk of lithium toxicity (this is the same for ketorolac therefore concomitant use must be avoided) 

• Venlafaxine:  there's  a possibility of increased serotonergic effects

• SSRIs: lithium toxicity has been reported. There's an increased risk of CNS effects

• TCAs: there's a risk of toxicity 

 

Lithium in: 

Pregnancy:  

 

• Must be avoided, especially in the 1st trimester unless necessary : risks include teratogenicity 

       and cardiac abnormalities 

• During the  2nd and 3rd semester, the dose is increased

• Post delivery, the normal dose is administered thereafter 

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​Breast feeding :

AVOID as present in milk and there is risk of TOXICITY in neonate

 

Renal impairment:

If possible lithium should be avoided in renal patients, or the dose should be reduced and serum-lithium concentration should be monitored  because lithium is renally excreted 

 

Lithium overdose 

• Lithium overdose in any patient who is taking it long term can be potentially serious 

• A once off overdose is usually deemed to be low risk where patients will suffer from mild-moderate symtoms regardless of their serum lithium concentration 

• However, severe symptoms can arise if lithium elimination s reduced due to renal impairment especially if a slow release formulation has been modified . A fatal dose (of  a single administration) is thought to be approximately over 5g. 

 

Lithium toxicity can also occur in (chronic accumulation) from the following situations: 

• Acute/chronic overdose 

• Dehydration 

• Worsening/poor renal function 

• Drug interactions: typically where a Non Steroidal Anti-Inflammatory Drugs  (NSAID) or a thiazide diuretic is involved 

 

Patients with a high lithium serum concentration are at a greater risk of suffering from toxicity if they suffer from any of the following

• Hypertension 

• Diabetes 

• Schizophrenia 

• Addison's disease 

• Congestive heart failure 

 

Symptoms of lithium toxicity 

Mild lithium toxicity 

• Nausea 

• Diarrhoea 

• Blurred vision 

• Drowsiness 

• Dizziness 

• Muscle weakness 

 

Moderate lithium toxicity 

• Hypernatraemia 

• More confusion 

• Myoclonic twitching and jerking 

• Urinary incontinence 

• Blackouts  

• Hypernatraemia 

• Increased deep tendon reflexes

• Increased restlessness followed by stupor 

 

Severe lithium toxicity 

• Coma

• Hypotension 

• Rarely hypertension 

• Convulsions 

• Cerebellar signs 

• Renal failure 

• Circulatory collapse 

• Cardiac dysrhythmias including sino-atrial block,

• Sinus and junctional bradycardia and first degree heart block.