Educational content. This article does not provide dosing, sourcing or buying information. If someone is unresponsive or struggling to breathe, call your emergency number now (112 in the EU, 999 in the UK, 911 in the US).
Designer benzodiazepines are unlicensed chemical relatives of prescription sedatives such as diazepam (Valium) and alprazolam (Xanax). They are sold online as “research chemicals” in powders, pellets and blotters, and increasingly turn up in counterfeit tablets made to look like real medicines. Names seen on the market include bromazolam, flubromazepam, flualprazolam, flubrotizolam, clonazolam, etizolam, norflurazepam, pyrazolam, deschloroetizolam and bromonordiazepam. Most have never been approved as medicines anywhere, and almost none have been studied properly in humans.
How they affect the body
Like prescription benzodiazepines, these drugs enhance the effect of GABA, the brain’s main “brake” chemical. That slows down the central nervous system, producing sedation, muscle relaxation, reduced anxiety and memory loss. A 2021 toxicology review notes that structural changes in newer designer benzodiazepines increase their binding to GABA-A receptors, so they produce strong sedation and amnesia and raise the risk of breathing failure.
Common side effects
- Heavy drowsiness, slurred speech and poor coordination
- Blackouts: long periods with no memory, sometimes lasting many hours
- Confusion and disinhibition, leading to risky or out-of-character behaviour
- Dizziness, falls and injuries
- Seriously impaired driving: the same review found designer benzodiazepines in a large share of drug-driving cases reported internationally
Why designer benzodiazepines are so dangerous
1. Unpredictable strength and content
These products come from unregulated labs. Studies have found that products can contain variable amounts of active ingredient or contaminants, including novel synthetic opioids, without the buyer knowing. Pellets, blotters and powders are not tested to pharmaceutical standards.
2. Breathing can stop when mixed with other depressants
Combining benzodiazepines with opioids, alcohol, GHB, pregabalin or gabapentin sharply increases the risk of respiratory depression, coma and death. Most deaths involving designer benzodiazepines involve more than one substance. In parts of North America, bromazolam is now frequently found alongside fentanyl in fatal overdoses, and naloxone (which reverses opioids) does not reverse benzodiazepine sedation.
3. Counterfeit “Xanax” and other fake pills
Tablets sold as alprazolam or diazepam have been found to contain etizolam, flualprazolam and other designer benzodiazepines. Seizures of such counterfeit tablets have been reported in the US, Australia and parts of Asia. A pill that looks like a known medicine is no guarantee of what it contains.
4. Long-lasting effects and repeated dosing
Some designer benzodiazepines stay active far longer than people expect. Because effects can feel delayed or wear off subjectively while the drug is still active, people sometimes take more, which builds up dangerously in the body.
5. Dependence and dangerous withdrawal
All benzodiazepines can cause tolerance and dependence, sometimes within weeks of regular use. Stopping suddenly after regular use can cause severe anxiety, insomnia, tremor, hallucinations and seizures, which can be life-threatening. Anyone who has used benzodiazepines regularly should not stop abruptly without medical support.
Overdose warning signs
- Cannot be woken, or only briefly
- Slow, shallow or noisy breathing; snoring-like sounds
- Blue or grey lips and fingertips
- Very slow heart rate or cold, clammy skin
- Seizures
What to do: call emergency services, place the person in the recovery position, stay with them, and tell responders everything they may have taken. If opioids could be involved, give naloxone if available; it will not reverse the benzodiazepine but can treat any opioid component.
Legal status
Many designer benzodiazepines are now controlled. Several, including etizolam and flualprazolam, are under international control, and countries such as the UK and US have scheduled many others. In the UK, the Psychoactive Substances Act 2016 also bans the supply of psychoactive substances not otherwise controlled. Labels such as “research chemical” or “not for human consumption” do not change a substance’s legal status.
Where to get help
- Emergency: 112 (EU), 999 (UK), 911 (US).
- Netherlands: Drugs Infolijn, Trimbos Institute (drugsinfo.nl); anonymous drug testing via DIMS.
- UK: FRANK (talktofrank.com).
- US: SAMHSA National Helpline, 1-800-662-4357 (free, confidential, 24/7).
- Your doctor or local addiction service for support with dependence or safe withdrawal.
For more on the wider market, read what “research chemicals” really are.
Frequently asked questions
Are designer benzodiazepines the same as prescription benzodiazepines?
No. They are related chemically but are not approved medicines, have not been properly tested in humans, and their strength and purity are unknown.
Can naloxone reverse a benzodiazepine overdose?
No. Naloxone only reverses opioids. It is still worth giving if opioids might be involved, but the person needs emergency care.
Is it dangerous to stop taking them?
After regular use, stopping suddenly can cause seizures. Seek medical help to reduce safely.
This article is for general information and does not replace medical advice.
