What is the recommended starting dose of Prozac (fluoxetine) for a 13-year-old?

Starting Dose of Prozac (Fluoxetine) for a 13-Year-Old

For a 13-year-old starting fluoxetine, begin with 10 mg/day for the first 2 weeks, then increase to the target maintenance dose of 20 mg/day. 1, 2

Initial Dosing Strategy

• Start at 10 mg/day for adolescents and higher weight children to minimize the risk of adverse events including behavioral activation, agitation, and suicidal ideation 2
• After 2 weeks at 10 mg/day, increase to 20 mg/day, which is the effective maintenance dose for most adolescents 1, 2
• The FDA-approved dosing for pediatric OCD (which provides guidance for adolescent dosing) specifically recommends this 10 mg starting dose for adolescents, followed by titration to 20 mg after 2 weeks 2

Critical Safety Monitoring

• Close monitoring is essential during the first few months of treatment and whenever doses are changed, particularly in the first 24-48 hours after dosage adjustments 1, 3
• Monitor specifically for:
  • Suicidal ideation or behavior 1, 3
  • Behavioral activation or agitation 1, 3
  • Switch to mania 3
• Starting at higher doses increases the risk of deliberate self-harm and/or suicide 1

Dose Titration Considerations

• Additional dose increases beyond 20 mg/day may be considered after several more weeks if insufficient clinical improvement is observed 2
• The recommended dose range is 20 to 60 mg/day for adolescents 2
• Fluoxetine has a very long half-life, so side effects may not manifest for a few weeks; therefore, increase doses slowly at approximately 3-4 week intervals 3
• Fluoxetine is activating, which makes the gradual titration approach particularly important 3

Important Clinical Pearls

• Fluoxetine is the only SSRI approved by the FDA for use in children and adolescents with depression 1
• The 20 mg/day dose is generally effective for most adolescents and should be the target maintenance dose 1
• If anxiety or agitation is a particular concern, consider starting with an even lower "test" dose and titrating more slowly 3
• When discontinuing, taper slowly over several weeks to avoid withdrawal symptoms, though fluoxetine's long half-life makes discontinuation syndrome less likely than with shorter-acting SSRIs 1, 3