Synthetically manufactured designer benzodiazepines can produce unknown biological effects and health risks in their attempt to mimic ordinary prescribed benzodiazepines such as alprazolam (Xanax®), clonazepam (Klonopin®), and diazepam (Valium®) which inhibit the neurotransmitter GABA to sedate or calm the user. Potent at low doses, designer benzodiazepines such as flualprazolam are strong sedatives that can cause loss of coordination, dizziness, drowsiness, amnesia, blurred vision, slurred speech, and in some situations, death.

Combining any prescribed or illicit benzodiazepines with opioids or depressants increases their collective potency and toxicity. As an example, because they all depress the central nervous system, taking benzodiazepines with alcohol or opiates like heroin increases the risk of drug overdose.

Until 2016, benzodiazepines were often prescribed to patients in combination with opioids, a practice now recognized as problematic because the combination can impair cognitive reasoning and interfere with breathing; a major cause of fatalities associated with overdose of compounds within the two drug classes. Studies further confirmed an increase of hospitalization when patients combined prescribed opioids with prescribed benzodiazepines. To complicate matters, designer benzodiazepine tablets and powders are often mixed with other benzodiazepines, opioids, and other unknown illicit street drugs.

As a leading national forensic toxicology laboratory, NMS Labs conducts forensic and clinical toxicology testing for various derived, synthetic, or designer benzodiazepines. Since 2015, global reporting trends indicate an increase in the availability and variety of these new psychoactive substances with as many as 30 currently being distributed and actively monitored, usually as substitutes for legitimate anti-anxiety prescription medication such as alprazolam (Xanax®) and diazepam (Valium®).