Issues About Axial Diffusion During Segmental Hair Analysis
May 2013
in “
Therapeutic drug monitoring
”
Studysummary This study explores the complexities of interpreting single drug exposure in hair, emphasizing factors like drug distribution variability and suggests methods to validate single exposure findings in forensic cases.
Our plain-language summary. Not medical advice or a treatment recommendation. Consult a qualified healthcare professional before changing treatment. Full disclaimer
The document discussed the challenges of interpreting drug exposure results from segmental hair analysis, particularly when drugs are detected in multiple consecutive hair segments. Based on 20 years of experience and literature review, the author suggested waiting 4-5 weeks post-event before collecting hair samples and segmenting them into 2 cm sections. A single drug dose should primarily appear in the proximal segment. However, drugs sometimes appear in multiple segments due to axial diffusion, sweat, and other secretions, or cosmetic treatments. To confirm single exposure, the highest drug concentration should be in the segment corresponding to the event period and be at least 3 times higher than adjacent segments.
