At what age can a pediatric patient with a mood disorder be started on a mood stabilizer, such as lithium (lithium) or valproate (valproic acid)?

Age Guidelines for Starting Mood Stabilizers in Pediatric Patients

Lithium can be started at age 12 and older, making it the only FDA-approved mood stabilizer for pediatric bipolar disorder in this age range. 1, 2, 3

FDA-Approved Age Thresholds

Lithium (First-Line Option)

• FDA-approved from age 12 years and older for both acute mania and maintenance therapy in bipolar disorder 1, 2
• In France, lithium is approved from age 16, though US approval begins at age 12 2
• Lithium demonstrates response rates of 38-62% in acute mania and shows superior evidence for long-term efficacy compared to other agents 1
• Lithium uniquely reduces suicide attempts 8.6-fold and completed suicides 9-fold, an effect independent of its mood-stabilizing properties 1

Atypical Antipsychotics (Alternative First-Line Options)

• Aripiprazole: FDA-approved from age 10 for acute mania and preventive treatment in the US; from age 13 in France 1, 2
• Risperidone and Quetiapine: FDA-approved from age 10 for acute mania 2
• Olanzapine: FDA-approved from age 13 for acute mania 2
• The American Academy of Child and Adolescent Psychiatry recommends atypical antipsychotics (aripiprazole, olanzapine, risperidone, quetiapine, ziprasidone) as first-line options for acute mania/mixed episodes 1

Anticonvulsants (Off-Label Use)

Valproate

• No FDA approval for any pediatric age, but the American Academy of Child and Adolescent Psychiatry recommends it as a first-line treatment for mania in adolescents 1, 2
• Shows higher response rates (53%) compared to lithium (38%) in children and adolescents with mania and mixed episodes 1
• Critical caveat: Should not be used in females of childbearing age due to teratogenic effects and risk of polycystic ovary disease 1, 2

Other Anticonvulsants

• Carbamazepine: Not recommended as first-line in adolescents despite adult approval, with only 38% response rates and risk of agranulocytosis 1, 2
• Lamotrigine: No pediatric approval, though used clinically for bipolar depression in adolescents with careful monitoring for Stevens-Johnson syndrome 1, 2

Clinical Decision Algorithm by Age

Ages 10-11 Years

• Start with atypical antipsychotics only (aripiprazole, risperidone, or quetiapine) 2
• Lithium and valproate are not FDA-approved in this age range 2

Ages 12+ Years

• Lithium becomes the preferred first-line option due to FDA approval and superior long-term efficacy 1, 2
• Alternative: Atypical antipsychotics (aripiprazole, risperidone, quetiapine) 1, 2
• Valproate can be considered off-label, particularly for mixed episodes or when lithium is contraindicated 1, 2

Ages 13+ Years

• All options available, including olanzapine 2
• Combination therapy (lithium or valproate plus atypical antipsychotic) should be considered for severe presentations 1

Critical Monitoring Requirements by Agent

Lithium (Age 12+)

• Baseline: Complete blood count, thyroid function, urinalysis, BUN, creatinine, serum calcium, pregnancy test in females 1
• Ongoing: Lithium levels, renal and thyroid function every 3-6 months 1
• Target levels: 0.8-1.2 mEq/L for acute treatment 1
• Safety concern: Narrow therapeutic window requires excellent compliance; lithium overdoses can be lethal 1, 2

Valproate (Off-Label)

• Baseline: Liver function tests, complete blood count, pregnancy test 1
• Ongoing: Serum drug levels, hepatic function, hematological indices every 3-6 months 1, 2
• Target levels: 50-100 μg/mL 1

Atypical Antipsychotics (Age 10-13+ depending on agent)

• Baseline: BMI, waist circumference, blood pressure, fasting glucose, fasting lipid panel 1
• Ongoing: BMI monthly for 3 months then quarterly; blood pressure, glucose, lipids at 3 months then yearly 1
• Major concern: Metabolic side effects (weight gain, diabetes risk) are more frequent in adolescents than adults 2

Common Pitfalls to Avoid

• Never use antidepressant monotherapy in pediatric bipolar disorder due to risk of mood destabilization and mania induction 1
• Avoid premature discontinuation of maintenance therapy—over 90% of noncompliant adolescents relapsed versus 37.5% of compliant patients 1
• Do not underestimate compliance challenges in adolescents—compliance rates are less than 40% in this population 2
• Never rapid-load lamotrigine if used off-label, as this dramatically increases Stevens-Johnson syndrome risk 1, 2
• Avoid typical antipsychotics (haloperidol, fluphenazine) due to 50% risk of tardive dyskinesia after 2 years in young patients 1

Maintenance Therapy Duration

• Continue treatment for at least 12-24 months after mood stabilization 1, 4
• Some patients will require lifelong treatment, particularly those with multiple severe episodes or rapid cycling 1
• Withdrawal of lithium dramatically increases relapse risk, especially within 6 months of discontinuation 1