Category: Forensic Toxicology
Can a Urine Cannabinoid Result Measure Cannabis Withdrawal Severity?
Serial urine cannabinoid results showed a limited association with withdrawal symptoms in a selected inpatient population, but they did not provide a stand-alone measure of an individual’s symptoms or impairment. A positive urine result, a withdrawal assessment, and a determination of intoxication answer different questions. Claus and colleagues investigated 78…
Cannabis the Morning After: Why a Null Group Comparison Does Not Clear Every Driver
Testing frequent cannabis users the morning after smoking did not reveal worse average performance than controls on two cognitive tasks. Within the cannabis group, however, higher THC concentrations and higher-potency products were associated with poorer performance on selected measures. Those findings can coexist. Neither supports automatically labeling every driver impaired—or…
Starting Medical Cannabis After Age 50: What a Driving-Simulator Study Can Actually Establish
A small study of adults starting medical cannabis did not demonstrate a different change in simulated driving performance from matched controls over one month. It also did not establish that driving after cannabis is safe. The distinction matters when a study is offered to support an opinion about a particular…
Cannabis Tolerance Claims: Questions to Ask Before Relying on Expert Testimony
How to evaluate cannabis tolerance claims using a 122-person crossover study, with attention to measured functions, baseline comparisons and individual-case limits.
Total and Unbound Drug Concentrations: What a Fasting Study Could Not Resolve
A laboratory can quantify total drug in plasma while struggling to quantify the much smaller unbound portion. That difference can determine whether a pharmacokinetic study answers its question. A result reported as not statistically significant does not resolve the question when the measurements are too limited to detect a meaningful…
Midazolam Sedation Models: Why a Medication Association Does Not Prove Antagonism
A medication can be associated with a different drug response because of the condition it was prescribed to treat. That possibility matters when interpreting a concentration-response model as evidence of a pharmacodynamic interaction. Franken and colleagues examined this problem in a study of midazolam sedation in terminally ill adults. Their…
CBD After Repeated Dosing: Why Detectability Does Not Establish a Washout Deadline
A cannabinoid detected after dosing stops is evidence of analytical persistence. It does not, by itself, establish an exact elimination half-life, the time of the last dose or a universal date when another person’s sample will test negative. A controlled study by Wolinsky and colleagues helps explain the distinction. Published…
Methamphetamine and Attention: Two Studies Showing Measured Performance Improvements
Two controlled studies measured improved divided-attention performance after methamphetamine administration. What those findings mean for forensic interpretation.
Oral THC and CBD Together: Why Formulation Matters
Research comparing oral THC administered in different cannabinoid formulations highlights the need to evaluate pharmacokinetics and pharmacodynamics togeth
Alcohol and the Brain: Why “Impairment” Is a Collection of Effects, Not a Single Switch
Research on visual processing, cerebral blood-flow responses, auditory attention, and interhemispheric inhibition shows why alcohol impairment is domain-specific.
Kratom Cardiac Arrest and the Limits of a Mitragynine Blood Level
A 500 µg/L mitragynine result in a survived cardiac arrest illustrates why concentration, treatment, specimen timing, and alternative causes matter.
Postmortem Alcohol Evidence: A Litigation Records and Source-Attribution Checklist
A litigation-focused guide to postmortem alcohol evidence, including specimen source, preservation, alternative matrices, biomarkers, higher alcohols, laboratory records, and questions for experts.
