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Drug Facts: Benzodiazepines & Related Compounds

AKA: Benzos, tranx, sleepers, downers. Specific drugs are referred to by their chemical name, brand name, and some have got slang names. Brand names vary around the world adding to confusion so for example the drug Diazepam is known by the brand name Valium in the UK, but is also known internationally by many other trade names including Mano, Anxol, Placidox and many other.

 Related Compounds: Benzodiazepines are linked by a common chemical structure. Closely related compounds include the thienodiazepines, and other similar drugs which aren’t strictly benzos as they have a different chemical structure. The reasons for use and risks are however likely to be the same. Likewise, closely related compounds such as the “Z-drugs” (e.g. Zopiclone and Zimovane) are not benzos but for treatment and harm-reduction purposes are interchangeable.

 More common benzodiazepines include:







 Xs, Xans

Not an NHS stock drug;

Available in UK on private prescription




Primarily used in in alcohol detox



Vallies, blues

Widely prescribed for daytime anxiety



Rohies, rufies

 Strong associations with drink spiking







temazies, jellies, eggs

Used to be widely injected




Widely available as an illicit benzo;
not prescribed in UK

 Source: Benzodiazepines are widely prescribed as sedatives, to combat anxiety, as skeletal muscle relaxants, anti-epileptics and anti-convulsants. Benzodiazepines have always leaked on to the streets and are widely used outside of prescription settings.

 For a number of years an additional route for sourcing benzodiazepines was the overseas prescription market. A number of websites, located outside the UK, would offer an online “consultation” with a “doctor” and then a “prescription” would be issued and “benzos” supplied. In practice the variability of the supplied pills was massive and many of these websites have been shut down.

 From 2009, abandoned experimental benzodiazepines and novel ones appeared on the UK drugs market including etizolam, pyrazolam and flubromazepam. These were initially not covered by the MoDA and were legally sold on-line and via ‘head-shops.” These novel benzos were almost all brought under the MoDA in May 2017. Any not covered or emerging since then are automatically covered by the Psychoactive Substances Act 2016.

 At present the key sources of benzodiazepines in the UK are:

 Trends: GPs are regularly reminded not to over-prescribe benzodiazepines and those on long term prescriptions are meant to have these reviewed and where possible be tapered off their medication.

This approach has been nominally successful with a significant and sustained drop in benzodiazepine prescribing.

However as the charts below show in the first instance the drop in Benzo prescribing represented in part simply a shift from one sedating drug to another. Initially the Z drugs started to get used in place of Benzos. They were initially not controlled drugs and not perceived to be addictive.

 Subsequently further drops in benzo prescribing were balanced by increased use of the gabapentinoids.

graph of benzoz v pregabs

prescribing trends uk

Subsequently even though benzos and related drugs became harder to get through legitimate routes, the massive growth of legal benzos as part of the NPS scene and their subsequent consolidation as an illicit street drug has meant that in some areas illicit benzos are more of an issue now than leaked prescribed benzos.

 The CSEW Survey of UK drug trends says that 0.8% of 16-25 year olds disclosed use of benzos (2019/20). This figure is down from 2017/28. This figure probably under-represents the true picture. It may be that the nature of the questions posed and exclusion of key benzo-using populations (prisoners, homeless, hostels, bail hostels) means figure is less than accurate.

 Appearance: Raw benzodiazepines are generally white powders, which are then pressed into pills, put in capsules or put into ampoules with appropriate colour, coating, printing etc.

Most are distributed as tablets or capsules. A small number of unregulated compounds are sold as powders. Benzos may also turn up as a cut in other drugs, especially heroin. Overdoses linked to “strong heroin” or “fentanyl” in heroin often turn out to be benzos cuts.

A few also come in preparations for injection, such as Valium ampoules, which command a higher street value.

Different brands of drug will vary from company to company. Tablets will vary in colour, shape and markings.  The appearance of each drug varies widely so visual pill identification is difficult.

While it’s no guarantee that pills that are sold in intact foil strips with UK specific labelling are less likely to be counterfeit.

Drugs supplied loose, or in overseas packaging are more likely to be counterfeit.

benzo pillsThe mainstay of the street benzodiazepine market has, since the 80s, been diazepam. The most widespread and popular strength, a 10mg tablet, is often a scored blue tablet. As a result, people manufacturing tablets to sell as diazepam invariably produce a blue tablet. These can vary massively in consistency and strength. Some are merely white powders, dyed blue and compressed into tablets.


Alprazolam (Xanax) has become increasingly popular in the UK. As it is not widely prescribed on the NHS, Alprazolam sold in the UK may be from private prescriptions, overseas pharmacies, or grey-market tablets batched from raw alprazolam powder. These can vary greatly in strength and consistency. Alprazolam is typically sold as white, scored bars with XANAX printed on them.

 Cost: At a street level, benzodiazepines have a very low value, typically around 50p per tablet. Ampoules can cost 5 and are rarely available now. Depending on dose and quantity stronger pills like Xanax can sell for between 1-5 depending on claimed dose.

 Quality: If pills are genuine pharmacy product, quality is assured. However, it is impossible to correctly identify loose drugs in this family by eye, let alone assay the strength, so mistakes in strength and name are frequent amongst those purchasing non-medical products.

 With so many imported, fake, unlicensed and novel products entering the market, the risks with non-pharmacy products will increase. Products could contain something stronger, weaker or different.

 It is possible to send pills to a service like WEDINOS https://www.wedinos.org/

to find out which drug(s) are present in a batch. Whilst useful to identify compounds, WEDINOS doesn’t share information about dose or level of different compounds so is of limited benefit from a harm reduction or dependency/taper point of view. While the service may indicate a blue pill contains diazepam and etizolam it won’t say how many milligrams of each drug are present.

 WEDINOS analysis shows high level of variability of street benzos.  Less  than half of tested pills contained the intended drug in the case of Alprazolam or Diazepam submitted for testing.


[Source WEDINOS Annual Report 2021-22]

Methods of Use: Tablets are designed for oral use, though some users crush and inject tablets. As diazepam has very poor solubility in water this is damaging and not very effective. Diazepam itself is relatively short acting; on ingestion it is metabolised in to a long-acting metabolite nor-diazepam so the risk is that people need to redose more frequently if taking via routes other than swallowing. There are some reports of snorting, especially of novel, unregulated benzodiazepines.

 Detection: Immuno-assay (urine test) kits can detect a range of benzodiazepine metabolites and related compounds. They are not sensitive for all benzos.  This varies according to:

High dose, lower potency, longer acting benzos structurally closer to diazepam will show up on most tests.

Shorter acting drugs, highly potent drugs and drugs that produce other metabolites may not show up.

In situations where a person is adamant that they are using a benzo-type drug but the urine tests negative, it could be that this specific drug at this specific dose doesn’t show up on this specific urine test. Double checking via a different brand of test or, ideally, via GC/MS would be a better option.

Mechanism of Action: Benzodiazepines interact with the GABA system in the brain. The regulatory neurotransmitter gamma-amino butyric acid (GABA) plays a role in moderating electrical activity in the brain. As GABA levels increase, so electrical activity in relevant neurons goes down.

Some drugs, like GHB and Barbiturates, are GABA agonists (mimics). Benzodiazepines are not thought to be full GABA mimics. Instead, benzodiazepines bind to Benzodiazepine Receptors (BZ receptors) and appear to increase the regulatory effect of GABA. They need GABA, or a GABA-mimic present to work.

Specific benzodiazepines are believed to be more active at different BZ receptors. This may result in different benzos having greater or lesser sleep-inducing, muscle relaxing or anxiolytic effects.

 The system to an extent self-regulates. As electrical levels drop in the brain it reduces levels of GABA release. As GABA drops the benzos can’t work.

 Importantly, if a GABA-mimic (such as alcohol) was present this self-regulation system can’t work. The co-presence of a GABA mimic AND benzos means that brain activity can be reduced to dangerous or fatal levels.

 There are thought to be at least three different types of Benzodiazepine (BZ) receptor. These are thought to impact differently on sleep, muscle relaxation and anxiety. Specific benzos may bind to these receptors differently, making some drugs more useful for sleep, others for muscle spasm and for anxiety.

 Benzodiazepines are thought to mimic naturally-occurring brain chemicals, which have been described as endozepines. However how these chemicals may occur is poorly understood.

Reasons for Use: Benzodiazepines are still used medically for a range of conditions including:

 Anti-convulsants                  anti-anxiety (anxiolytic)       sleep-inducing (hypnotic)

muscle relaxant                    amnesiac                              alcohol detoxification

 Non-medical use follows similar patterns, self-medicating for a range of conditions including anxiety and insomnia. They are also popular as “come-down” drugs following use of stimulants. The sense of intoxication when used with opiates or alcohol is greater, so these combinations are widely used. This brings a bigger risk of overdose.

Benzodiazepines are moderately euphoric, especially in users who have little tolerance.

Benzos can help people not remember or remember without emotion making them popular choices for managing traumatic memories. They can create a sense of detachment, depersonalisation or “derealization,” making the real world feel less present or intrusive.

The sense of calm, detachment, well-being and relaxation from benzos makes them highly sought after amongst people experiencing negative mental health symptoms.

 Strength: Important: this information assumes that we know which benzo is being used. As street benzos are of unknown strength and purity this information cannot be used to work out dose equivalence for street benzos.

 Benzodiazepines vary significantly in strength. They are generally compared in potency using diazepam (Valium) as a benchmark. Potencies are expressed in relation to 10mg of diazepam. 5mg of Alprazolam (for example) is equivalent to 10mg of diazepam. Alprazolam is around twenty times the strength of diazepam.
Very strong benzos such as Flubromazolam are believed to be 40x the strength of Diazepam. If a pill contained 1mg of flubromazolam, this would be the equivalent of 40mg of diazepam (i.e. 4 x 10mg diazepam.)