Page last updated Dec. 14, 2023 by Doug McVay, Editor.

1. Dark Web and the Street Drug Market

"Highly anonymized, elusive, and unregulated, the Dark Web is an ideal landscape for vendors selling illicit substances. The substances, in addition to the markets themselves, that are available on the Dark Web at any given time are difficult to predict. To offer insight into and characterize Dark Web markets, we conducted a study of the substances available on the Dark Web, both historically—between 2012 and 2019—and at present, between 2022 and 2023. Therefore, the present study offers, to our knowledge, a first snapshot in time of the categorical and chronological distribution and availability of various illicit psychoactive substances on Dark Web cryptomarkets.

"These data are pertinent in the face of various overdose epidemics around the world and concurrent, ongoing changes in street drug markets, which pose challenges to the clinical system of care (Krausz et al., 2021). In North America, for example, market shifts have resulted in the increased availability of highly potent opioids like fentanyl, increasing the risk of overdose and death (Krausz et al., 2021). Unanticipated changes such as this can burden the healthcare system and lead to poor outcomes such as increased morbidity and mortality related to drug use by hindering the development of appropriate intervention and treatment (Krausz et al., 2021). In the absence of geographical limitations, fluctuations in Dark Web markets compared to street markets can pose an even greater and global threat to the healthcare systems designed to address substance-related issues.

"Given their globalized nature, cryptomarkets may offer predictive value with regard to changes in street markets for illicit substances. It is possible that the substances available on the Dark Web reflect their supply and demand across street markets. For instance, researchers have found that cryptomarkets are frequently used for wholesale purposes, whereby drug vendors across street markets may purchase substances online and then sell to individual customers at the offline, street level (Aldridge and Décary-Hétu, 2016). Understanding Dark Web markets would offer insight into the supply chain of illicit substances and potentially inform predictions surrounding which substances are likely to dominate street markets (Broadhurst et al., 2021)."

Sudan HK, Tai AMY, Kim J, Krausz RM. Decrypting the cryptomarkets: Trends over a decade of the Dark Web drug trade. Drug Science, Policy and Law. 2023;9. doi:10.1177/20503245231215668.

2. Estimated Size of Drug Markets on the Dark Web

"An Internet survey conducted simultaneously in 10 European Union countries in the period 2017–2018 among some 20,000 Internet-using drug consumers,15 using various recruitment strategies,16 found that 8 per cent of survey respondents had bought drugs on the dark web.17 This was a far smaller proportion than those who had bought drugs from a drug dealer (59 per cent), but a significantly larger proportion than those who had bought drugs from an online shop (3 per cent) or a specialized NPS shop (1 per cent).18 

"Another online survey, based on a convenience sample of more than 100,000 participants in 35 countries worldwide, suggested that the proportion of Internet-using drug consumers who had purchased drugs on the dark web in the previous 12 months had more than doubled between 2014 and 2022, from 4.7 to 10.8 per cent.19 Although plausible, these findings should be interpreted with caution, because they are not based on representative global samples but on convenience samples that are characterized by an overrepresentation of Internet users in Europe, the Americas and Oceania. 

"Estimating the size of drug markets on the dark web is challenging. An analysis of major darknet markets using web-crawling techniques has shown that they are highly volatile and have a propensity to disappear at short notice as a result of both law enforcement successes in dismantling such markets and exit scams.20 

"Another approach has been to systematically investigate the existing blockchains of various cryptocurrencies for suspicious addresses involved in illegal transactions, and the resulting money flows between such addresses (cryptocurrency wallets). The analysis of various blockchains of cryptocurrencies suggests that darknet markets (mostly selling drugs) continued growing up until 2021, when their combined revenue reached a record high of an estimated $2.7 billion (equivalent to an estimated 1.5 per cent of retail drug sales in North America and Europe),21 before declining by half, to around $1.3 billion in 2022, mostly as a result of the dismantling of the darknet platform Hydra Market in April 2022.22 Nonetheless, darknet markets continue to show resilience and started to recover in the second half of 2022."

UNODC. World Drug Report 2023. United Nations publication, 2023.

3. The Illegal Drug Trade on the Dark Web

"The Dark Web is a subsection of the internet that has become a hub for illicit activities, such as drug trafficking, money laundering, and weapons trading. The Dark Web offers extensive layers of anonymity, making it appealing for individuals to engage in criminal behavior (Gupta et al., 2019). For example, information exchange over the Dark Web differs from the rest of the internet by employing robust encryption techniques for information exchange (Gupta et al., 2019). Additionally, the Dark Web is characterized by a network of websites that are not indexed by search engines, rendering it accessible exclusively through specialized software and browsers like The Onion Router (TOR) (Gupta et al., 2019).

"The illicit drug trade on the Dark Web poses unique risks to public health and safety. Substances available on the Dark Web are unregulated and untraceable and, unlike traditional drug markets, are not geographically limited. Therefore, the Dark Web provides a global platform for drug trafficking. This has resulted in an increase in the availability and accessibility of illicit drugs, which may have contributed to drug epidemics around the world. The illicit drug trade on the Dark Web takes place on cryptomarkets, characterized by their use of cryptocurrency (e.g., Bitcoin) for payment (ElBahrawy et al., 2020). This form of payment is nearly untraceable and allows those selling and purchasing drugs on the Dark Web to evade law enforcement (Kumar and Rosenbach, 2019)."

Sudan HK, Tai AMY, Kim J, Krausz RM. Decrypting the cryptomarkets: Trends over a decade of the Dark Web drug trade. Drug Science, Policy and Law. 2023;9. doi:10.1177/20503245231215668.

4. Dark Net Drug Markets and Cryptomarkets

"The internet has facilitated the sale of licit and illicit drugs for more than 15 years,10 11 12 13 but when the first cryptomarket, Silk Road 1, came online in 2011, illicit drugs began to be traded in large quantities. The annual turnover of drug sales conducted through cryptomarkets is estimated to be in the hundreds of millions of dollars,14 with most transactions involving recreational drugs (eg, cannabis, “ecstasy”). Before 2014, prescription drugs represented slightly less than 10% of all cryptomarket sales.14 15 People who buy through cryptomarkets are believed to be predominantly male, young (<25 years), educated, employed, and white.16 17 18 19 20 21

"Since 2011, cryptomarkets have been analysed through the digital traces they leave online,22 using automated software “crawlers” that collect publicly available data hosted on websites. The wealth of data available to researchers employing digital trace analysis includes the aliases and purported country level locations of drug vendors and the countries to which they are willing to make shipments. From each product listing posted by vendors on the marketplace, the drug type, price, and quantity can be determined, alongside customer feedback. Using these data, researchers have been able to track the growth of drug trading through the darknet,14 15 determining overall size, composition, and geographical distribution.20 23 24 25 Feedback posted by customers are used by researchers as a proxy for estimating numbers of transactions and revenues generated by drug vendors."

Martin J, Cunliffe J, Décary-Hétu D, Aldridge J. Effect of restricting the legal supply of prescription opioids on buying through online illicit marketplaces: interrupted time series analysis. The BMJ. 2018;361:k2270. doi:10.1136/bmj.k2270.

5. Law Enforcement Largely Ineffective Against Illegal Dark Net Markets

"In July 2017, police forces from several countries worked together to take down the largest drug-trading platform on the darknet, the part of the “deep web” containing information that is only accessible using special web browsers. Before it was closed, AlphaBay had featured more than 250,000 listings for illegal drugs and chemicals. It had had over 200,000 users and 40,000 vendors during its existence. The authorities also succeeded in taking down the trading platform Hansa, described as the third largest criminal marketplace on the dark web.

"It is not yet clear what effect the closures will have. According to an online survey in January 2018, 15 per cent of those who had used darknet sites for purchasing drugs said that they had used such markets less frequently since the closures, and 9 per cent said they had completely stopped. However, more than half did not consider themselves to have been affected by the closures.

"Although the scale of drug trafficking on the darknet remains limited, it has shown signs of rapid growth. Authorities in Europe estimated that drug sales on the darknet from 22 November 2011 to 16 February 2015 amounted to roughly $44 million per year. However, a later study estimated that, in early 2016, drug sales on the darknet were between $14 million and $25 million per month, equivalent to between $170 million and $300 million per year."

World Drug Report 2018. United Nations publication, Sales No. E.18.XI.9.

6. Changes in Dark Web Drug Markets

"Descriptive analysis of the data collected through both the literature review and data scraping on the Dark Web indicated varying periods of volatility in the availability and distribution of psychoactive substances. Notably, no major changes were apparent in the distribution of substances, on average, between 2012 and 2019, as reported in the literature.

"Contrarily, the novel data collected in this study from 13 cryptomarkets between late 2022 and early 2023 showed that there was a relative change in the distribution of substances from data reported in 2012 to 2019. Specifically, the category of prescription drugs decreased in proportion, becoming the second smallest proportion of listings, from over 20% between 2012 and 2019 to under 5% between 2022 and 2023. In addition, opioid listings seemingly doubled, growing from 5.5% to 9.25%."

Sudan HK, Tai AMY, Kim J, Krausz RM. Decrypting the cryptomarkets: Trends over a decade of the Dark Web drug trade. Drug Science, Policy and Law. 2023;9. doi:10.1177/20503245231215668.

7. Drug Policies and the Dark Web

"The increasing availability of potent substances such as opioids on the Dark Web indicates that the current drug policies are ineffective. Criminalizing drug use facilitates opportunities for illicit drug markets to operate both on the streets and online, including highly elusive spaces like the Dark Web. As found in this study, despite efforts to curb the availability of illicit substances on the Dark Web, cryptomarkets list these substances for sale in abundance. The harms associated with the illicit drug trade may be mitigated by decriminalization of substance use and the availability of a regulated safe supply of psychoactive substances."

Sudan HK, Tai AMY, Kim J, Krausz RM. Decrypting the cryptomarkets: Trends over a decade of the Dark Web drug trade. Drug Science, Policy and Law. 2023;9. doi:10.1177/20503245231215668.

8. Drugs and Social Media

"End users seem to be buying their drugs on the dark web to a lesser extent than in previous years.28 Qualitative information provided by people who use social media suggests that the use of such media for drug purchasing purposes has been increasing, especially at the retail level.29 This is occurring in a context in which the use of social media, typically accessed via the clear web (although not exclusively) is increasing more rapidly than the use of the Internet in general. 

"In a study conducted in the United States (2018) and Spain (2019), in which about one tenth of all Internet-using drug consumers aged 15–25 bought drugs online, large proportions (69 per cent in the United States and 86 per cent in Spain) of online purchases were made via social media, and the remainder on darknet markets.30 Another study, conducted in Ireland in 2021, suggested that around 64 per cent of online drug purchases among the general population were made using social media, 28 per cent occurred on darknet markets and 8 per cent were made via online shops.31 That pattern applied to most drug types.32 A previous comparison of social media and darknet markets in Denmark, carried out in 2017, had also suggested that most online drug purchases were made via social media (71 per cent).33 

"Drugs are sold on a number of social media platforms, including mainstream platforms such as Facebook, Instagram, Snapchat and WhatsApp.34 Platforms that enable social networking between strangers, such as Tinder, Grindr, Instagram, Facebook and Discord, allow sellers to openly “advertise” their products to unknown buyers by constructing a public profile. Conversely, messaging platforms, both encrypted and unencrypted, facilitate more private drug transactions between people who already know one another, via direct message or within the confines of a group chat.35 

"The two main social media platforms identified for drug purchases in the above-mentioned study conducted in the United States and Spain in 2018/2019 were Facebook and Instagram.36 Findings from a study in Nordic countries in the period September–December 2017 show that Facebook and Instagram were also the social media platforms most commonly used for drug dealing in Denmark, Iceland and Sweden. There were no indications of drug dealing on open social media platforms such as Facebook in Norway, however. The same was true in Finland, where the majority of online drug purchases were made on darknet markets. One-on-one social media forums such as Reddit seem to be preferred in Norway.37 However, different social media platforms may also be used for different drugs, as seen in Latin America and the Caribbean.38"

UNODC. World Drug Report 2023. United Nations publication, 2023.

9. Tightened Restrictions on Legal Prescription Hydrocodone Led to Increase in Illegal Sales

"Objective: To examine the effect on the trade in opioids through online illicit markets (“cryptomarkets”) of the US Drug Enforcement Administration’s ruling in 2014 to reschedule hydrocodone combination products.

"Design: Interrupted time series analysis.

"Setting: 31 of the world’s largest cryptomarkets operating from October 2013 to July 2016.

"Main outcome measures: The proportion of total transactions, advertised and active listings for prescription opioids, prescription sedatives, prescription steroids, prescription stimulants, and illicit opioids, and the composition of the prescription opioid market between the US and elsewhere.

"Results: The sale of prescription opioids through US cryptomarkets increased after the schedule change, with no statistically significant changes in sales of prescription sedatives, prescription steroids, prescription stimulants, or illicit opioids. In July 2016 sales of opioids through US cryptomarkets represented 13.7% of all drug sales (95% confidence interval 11.5% to 16.0%) compared with a modelled estimate of 6.7% of all sales (3.7% to 9.6%) had the new schedule not been introduced. This corresponds to a 4 percentage point yearly increase in the amount of trade that prescription opioids represent in the US market, set against no corresponding changes for comparable products or for prescription opioids sold outside the US. This change was first observed for sales, and later observed for product availability. There was also a change in the composition of the prescription opioid market: fentanyl was the least purchased product during July to September 2014, then the second most frequently purchased by July 2016.

"Conclusions: The scheduling change in hydrocodone combination products coincided with a statistically significant, sustained increase in illicit trading of opioids through online US cryptomarkets. These changes were not observed for other drug groups or in other countries. A subsequent move was observed towards the purchase of more potent forms of prescription opioids, particularly oxycodone and fentanyl."

Martin James, Cunliffe Jack, Décary-Hétu David, Aldridge Judith. Effect of restricting the legal supply of prescription opioids on buying through online illicit marketplaces: interrupted time series analysis. British Medical Journal. 2018; 361:k2270.

10. Harm Reduction and the Dark Web

"Darknet-based drug marketplaces are frequently used by PWUD. 'Empire Market' [13], 'Hydra' (in Russia) [14] and other darknet markets operate similarly to regular online marketplaces: they give vendors and buyers a platform to conduct their online transactions on. However, darknet-based drug marketplaces are more difficult to access as they require special software which encrypts computer IP addresses (e.g., Tor Browser). Transactions are anonymized and performed with cryptocurrencies (e.g., Bitcoin); hence, darknet markets are also called ‘cryptomarkets’. In addition to making purchases on the cryptomarkets, users can also exchange information on the availability of particular drugs, experiences from using them, their effects and potential harms via integrated online forums [15–17].

"The use of drug marketplaces and drug-related online forums to facilitate harm reduction has started to gain the attention of researchers. A number of studies have shown that such online platforms could bring new opportunities to provision of harm reduction services [18–20]. Social media platforms have also shown potential to bring greater access to harm reduction services among PWUD [People Who Use Drugs] [21]. Harm reduction interventions via online platforms are often referred to as ‘web outreach’, ‘online outreach’ or ‘netreach’ work [22, 23].

"Web outreach work implies that harm reduction workers contact PWUD through online platforms and provide them with harm reduction information and counseling upon individual requests of users or distribute harm reduction information publicly via online forums. Such work helps to encourage risk reduction behaviors among hard-to-reach populations of PWUD, who do not attend brick-and-mortar harm reduction facilities [22, 23]. Moreover, the COVID-19 pandemic has introduced social distancing measures and shortages of medicines and harm reduction supplies, which makes it more difficult to provide in-person harm reduction services [24, 25]. Web outreach helps organizations continue to provide harm reduction services during the pandemic."

Davitadze, A., Meylakhs, P., Lakhov, A. et al. Harm reduction via online platforms for people who use drugs in Russia: a qualitative analysis of web outreach work. Harm Reduct J 17, 98 (2020).