What is the recommended dose of fluoxetine (selective serotonin reuptake inhibitor) for a 12-year-old girl weighing 63kg?

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From the Guidelines

For a 12-year-old girl weighing 63kg, the recommended starting dose of fluoxetine is 10mg once daily, with potential increase to 20mg daily after 1-2 weeks if clinically indicated. This recommendation is based on the study by Hollander et al., 2005 1, which reported a mean dose of 9.9 mg/d for children aged 5-17 years old. Although the study did not provide a specific dose for a 12-year-old girl weighing 63kg, the recommended dose range for fluoxetine in children is generally between 5-20 mg/day, as reported in the study by 1.

The medication should be taken in the morning to minimize sleep disturbances. Treatment response typically takes 2-4 weeks to become apparent, and if effective, treatment should continue for at least 6-9 months to prevent relapse. Common side effects include nausea, headache, insomnia, and potential initial increase in anxiety or agitation. Close monitoring is essential during the first few weeks of treatment due to a small increased risk of suicidal thoughts in pediatric patients starting SSRIs.

Some key points to consider when prescribing fluoxetine to a 12-year-old girl include:

  • The dosing is not strictly weight-based in this age group but rather age-appropriate, with careful titration based on clinical response and tolerability.
  • Fluoxetine works by increasing serotonin levels in the brain by blocking its reuptake, which helps regulate mood, anxiety, and obsessive thoughts.
  • The study by Hollander et al., 2005 1 reported a statistically significant decrease in repetitive behavior on the CY-BOCS Compulsions scale, indicating the effectiveness of fluoxetine in treating obsessive-compulsive disorder in children.
  • The study by 1 reported that doses of fluoxetine ranging from 5 to 20 mg/day are effective in delaying ejaculation and enhancing patient/partner satisfaction, although this study was focused on the treatment of premature ejaculation in men.

Overall, the recommended starting dose of fluoxetine for a 12-year-old girl weighing 63kg is 10mg once daily, with careful monitoring and potential increase to 20mg daily after 1-2 weeks if clinically indicated.

From the FDA Drug Label

Pediatric (children and adolescents) — In the short–term (8 to 9 week) controlled clinical trials of fluoxetine supporting its effectiveness in the treatment of major depressive disorder, patients were administered fluoxetine doses of 10 to 20 mg/day However, due to higher plasma levels in lower weight children, the starting and target dose in this group may be 10 mg/day. A dose increase to 20 mg/day may be considered after several weeks if insufficient clinical improvement is observed

The recommended dose of fluoxetine for a 12-year-old girl weighing 63kg is 10 to 20 mg/day.

  • The dose may be initiated at 10 mg/day and increased to 20 mg/day after several weeks if insufficient clinical improvement is observed. 2

From the Research

Recommended Dose of Fluoxetine for a 12-Year-Old Girl

The recommended dose of fluoxetine for a 12-year-old girl weighing 63kg is not explicitly stated in the provided studies. However, the following information can be gathered:

  • The study 3 mentions that fluoxetine was administered at a dose of 10 to 40 mg/d in the Treatment for Adolescents With Depression Study (TADS) randomized controlled trial.
  • The study 4 compares the efficacy, acceptability, and safety of various treatments for acute major depressive disorder in children and adolescents, including fluoxetine, but does not provide specific dosage information.
  • The study 5 discusses the combination of selective serotonin reuptake inhibitors (SSRIs) and cognitive behavioral therapy (CBT) in youth with depression and anxiety, but does not provide specific dosage information for fluoxetine.

Key Points to Consider

  • Fluoxetine is a commonly used SSRI for the treatment of depression in children and adolescents 6, 3, 4.
  • The combination of fluoxetine and CBT has been shown to be effective in treating depression in adolescents 3, 5.
  • The dosage of fluoxetine may vary depending on the individual patient and the specific treatment protocol 3.

Important Considerations

  • The studies provided do not offer a clear recommendation for the dose of fluoxetine for a 12-year-old girl weighing 63kg.
  • It is essential to consult with a healthcare professional to determine the appropriate dose of fluoxetine for a specific patient, taking into account their individual needs and medical history.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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