What is the safety profile of Qelbree (viloxazine)?

Safety Profile of Qelbree (Viloxazine)

Qelbree (viloxazine) has a safety profile characterized by common adverse effects including somnolence, decreased appetite, fatigue, nausea, vomiting, insomnia, and irritability, with limited data on its use during pregnancy and breastfeeding. 1

Key Safety Considerations

Cardiovascular Effects

• Blood pressure and heart rate monitoring required:
  • 13% of patients treated with Qelbree had ≥15 mmHg increase in diastolic blood pressure (vs. 9% with placebo) 1
  • Assessment of heart rate and blood pressure recommended:
    • Prior to initiating treatment
    • Following dose increases
    • Periodically during therapy 1

Psychiatric Effects

• Boxed warning for suicidal thoughts and behaviors similar to other ADHD nonstimulants 1, 2
• Risk of activation of mania/hypomania in patients with bipolar disorder 1
  • Screening for bipolar disorder recommended before treatment initiation
  • Detailed psychiatric history should include personal/family history of suicide, bipolar disorder, and depression 1

Neurological Effects

• Somnolence and fatigue are common adverse effects:
  • Somnolence (including lethargy and sedation): 16% in pediatric patients vs. 4% with placebo 1
  • Somnolence: 6% in adult patients vs. 2% with placebo 1
  • Fatigue: 6% in pediatric patients vs. 2% with placebo 1
  • Fatigue: 12% in adult patients vs. 3% with placebo 1
  • Patients should avoid activities requiring mental alertness until they know how Qelbree affects them 1

Gastrointestinal Effects

• Common adverse reactions include:
  • Nausea: reported in 5% of patients (vs. 1% with placebo) 1
  • Vomiting: reported in 4% of patients (vs. 2% with placebo) 1
  • Abdominal pain: reported in 5% of patients (vs. 4% with placebo) 1

Metabolic Effects

• Decreased appetite: reported in 7% of patients (vs. 0.4% with placebo) 1
• Effects on weight:
  • Children 6-11 years: gained average of 0.2 kg (vs. 1 kg with placebo) 1
  • Adolescents 12-17 years: lost average of 0.2 kg (vs. gain of 1.5 kg with placebo) 1

Long-term Safety Data

• In long-term open-label extension studies, viloxazine ER was generally well tolerated with no new safety concerns identified during extended use 3
• Most common adverse events in long-term adult studies (>10% incidence) included:
  • Insomnia (13.8%)
  • Nausea (13.8%)
  • Headache (10.7%)
  • Fatigue (10.1%) 3
• Discontinuation rate due to adverse events in long-term studies was 17.6%, most commonly due to insomnia (2.5%), nausea (2.5%), and fatigue (1.9%) 3

Special Populations

Pregnancy and Breastfeeding

• Limited data available on safety during pregnancy and breastfeeding:
  • No published studies of viloxazine in pregnancy 4
  • No published studies of viloxazine while breastfeeding 4
  • Should be used with caution after risk-benefit discussion 4
  • Alternative agents would be preferred in these populations 4

Comparison to Other ADHD Medications

• As a nonstimulant, viloxazine does not carry the abuse potential or physical dependence risks associated with stimulant medications 5
• Viloxazine appears to have a faster onset of action (1-2 weeks) compared to atomoxetine (4 weeks), though direct comparison studies are lacking 2
• Unlike alpha-2 agonists (clonidine, guanfacine), viloxazine's primary mechanism is as a selective norepinephrine reuptake inhibitor 5

Practical Considerations

• Dose titration should be gradual to minimize side effects
• Most adult patients in long-term studies used doses ≥400 mg/day (73%), with 36% using the maximum dose of 600 mg/day 3
• Treatment discontinuation rates due to adverse events in clinical trials were approximately 3% in pediatric patients 1 and 9% in adult patients 6

Monitoring Recommendations

• Before starting treatment:
  • Screen for bipolar disorder and suicide risk
  • Assess baseline heart rate and blood pressure
• During treatment:
  • Monitor for emergence of suicidal thoughts or behaviors
  • Check blood pressure and heart rate periodically
  • Assess for somnolence and fatigue that may impact daily functioning
  • Monitor weight, particularly in pediatric patients

Qelbree represents a useful non-stimulant option for ADHD treatment with a well-characterized safety profile, though caution is warranted regarding cardiovascular effects, psychiatric risks, and common side effects like somnolence and fatigue.