Mirtazapine in an 8-Year-Old Child
Mirtazapine should not be prescribed to an 8-year-old child for standard indications, as the FDA explicitly states that "mirtazapine tablets are not for use in children" and warns that children under 18 should not take mirtazapine. 1
FDA Position and Safety Concerns
The FDA drug label is unequivocal in its contraindication for pediatric use:
- Mirtazapine carries a black box warning for increased risk of suicidal thoughts or actions in children and young adults under 24 years of age, particularly within the first few months of treatment or when doses are changed 1
- The label explicitly states: "It is not known if mirtazapine tablets are safe and effective for use to treat MDD in children" 1
- Children under age 18 should not take mirtazapine according to FDA guidance 1
Limited Exception: Highly Specialized Circumstances Only
While the FDA position is clear, there are extremely narrow circumstances where mirtazapine might be considered:
- The American Academy of Pediatrics suggests mirtazapine may improve sleep disorders and behavioral symptoms in children with autism spectrum disorder, with doses of 7.5-45 mg daily showing efficacy in small studies 2
- One open-label pilot study included children as young as 8 years with social phobia, though this was investigational and showed significant tolerability concerns (61% did not complete 8 weeks, 22% discontinued due to adverse effects including fatigue and irritability, with significant weight gain observed) 3
- A case series reported mirtazapine use in children aged 6-16 years for chronic/cyclic vomiting syndromes with psychiatric comorbidity, using doses of 7.5-30 mg/day 4
Critical Safety Monitoring If Exceptionally Prescribed
If mirtazapine is considered in this highly specialized context (autism spectrum disorder with severe sleep/behavioral issues), the following monitoring is mandatory:
- Close surveillance for new or worsening suicidal thoughts, mood changes, agitation, irritability, or unusual behavior changes 1
- Frequent follow-up visits, especially in the first weeks of treatment 1
- Monitoring for sedation, increased appetite, and significant weight gain (common adverse effects) 3, 4
- Awareness that agranulocytosis and neutropenia, though rare, have been reported with mirtazapine 5
Preferred Alternatives
- For pediatric anxiety disorders, duloxetine (an SNRI) has FDA approval and should be considered as a preferred treatment option over mirtazapine 2
- For depression in children, other FDA-approved options should be exhausted before considering off-label mirtazapine use 1
Bottom Line
Unless treating a child with autism spectrum disorder under specialized psychiatric care for refractory sleep/behavioral symptoms where other options have failed, mirtazapine should not be prescribed to an 8-year-old. The FDA explicitly contraindicates its use in children, and the black box warning for suicidality in this age group makes it inappropriate for routine prescribing 1. Any exceptional use requires specialized psychiatric consultation, informed consent discussion about off-label use and suicide risk, and intensive monitoring protocols 1, 3.