What are the side effects of Brexanolone (allopregnanolone)?

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Brexanolone Side Effects

Brexanolone's most critical side effects are sudden loss of consciousness and excessive sedation, requiring continuous pulse oximetry monitoring during the entire 60-hour infusion, with additional common effects including dizziness, dry mouth, headache, and flushing. 1, 2

Serious Adverse Effects Requiring Monitoring

  • Loss of consciousness, presyncope, or syncope occurs in approximately 4% of patients, representing the most severe safety concern 1
  • Excessive sedation and somnolence are frequent enough to mandate continuous pulse oximetry throughout the infusion 2, 3
  • Due to these risks, brexanolone is only available through a Risk Evaluation and Mitigation Strategies (REMS) program, requiring administration in a supervised medical setting with continuous monitoring 1, 4

Common Adverse Effects

The most frequently reported side effects during clinical trials include:

  • Sedation - among the most common adverse events 1, 2
  • Dizziness - frequently reported across studies 1, 2
  • Dry mouth - common tolerability issue 2
  • Headache - frequently observed 1, 2
  • Flushing - noted in clinical trials 2
  • Somnolence - related to the drug's GABAergic mechanism 1

Clinical Management Considerations

  • Continuous pulse oximetry is mandatory throughout the entire 60-hour infusion period due to risks of sudden loss of consciousness and excessive sedation 2
  • Administration must occur in a certified healthcare facility with appropriate monitoring capabilities 4
  • The drug has an acceptable overall safety profile when administered with proper monitoring, with most adverse effects being manageable 2, 5

Tolerability Profile

  • Brexanolone was generally well-tolerated in all three pivotal clinical trials when administered with appropriate monitoring 2, 5
  • The adverse effects are primarily related to its mechanism as a positive allosteric modulator of GABAA receptors, enhancing inhibitory neurotransmission 3, 5
  • No serious adverse effects related to transmission of infectious agents or anaphylaxis have been reported, unlike some other intravenous therapies 2

References

Research

Brexanolone for postpartum depression.

American journal of health-system pharmacy : AJHP : official journal of the American Society of Health-System Pharmacists, 2020

Research

Use of Brexanolone for Postpartum Depression.

Innovations in clinical neuroscience, 2019

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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