This study found that HRDU is prevalent throughout Palestine. We estimated that there are approximately 26,500 HRDUs in Palestine, comprising 1.8% of the male population aged 15 and above. The 2017 United Nations Office on Drugs and Crime (UNODC) Global Drug Report claims that the number of illicit drug users (i.e., used any kind of illicit drugs at least once in the past year) is 7–10 times higher than the number of HRDUs. Adding 7% on top of our size estimation of 1.8% (26,500 HRDUs) would indicate that there are at least 9.0% (180,000) males who use illicit drugs aged 15 years and older in Palestine. It is worth noting that the estimated prevalence of ever drug use is much higher than the global prevalence of 5% of people (males and females) between the ages of 15 and 64 years who used drugs at least once in 2015, based on the UNODC Global Report 2017 [1].

Political and economic tension in Palestine has facilitated the spread of illicit drug use among Palestinians. In the context of house demolitions, arrests, restriction of movement and encroachment on land, illicit drugs have been used in Palestine as a ‘coping mechanism’. It provides youth with an opportunity to “escape problems”, obtain a “feeling of relaxation”, to “not think”, and to “fall asleep” [19]. Research on the use of tramadol in the Gaza Strip demonstrates that recurrent attacks and siege related to the Israeli occupation, as well as high unemployment among university graduates are factors associated with the widespread use of tramadol [20]. Similarly, violence and traumatic events experienced by children in the Gaza Strip related to the Israeli occupation is linked to increased illicit drug use among children [21]. In addition to political, economic, and social factors, regulatory and enforcement issues also contribute to the increase of illicit drug use in Palestine, which includes the absence of unified Palestinian authority and police system, internal political turmoil, weak legal enforcement, and limited border control to combat trafficking [22].

Many HRDUs were found to be using drugs, such as Tramadol and sedatives, that should be prescribed by a physician. Based on the UNODC drug report of 2021, there has been a rise in the non-medical use of pharmaceutical drugs between 1995 and 2019 [1]. We found that almost all HRDUs in the Gaza Strip (99%) had used Tramadol (verified through urinalysis) and Lyrica (54%) in the previous month. Although Tramadol and Lyrica are not considered to have the same addiction risk as other narcotics, they are still addictive when used frequently and in high doses [22]. Lyrica was only used in the Gaza Strip. As Lyrica was not yet among the the list of controlled drugs at the time of this study, it was being used instead of Tramadol. Tramadol was classified as a controlled drug, its use was crminalized, and offenders were imprisoned and had to pay to large penalties for each arrest related to Tramadol use .

The majority of HRDUs in the West Bank (south [88%], north [83%], middle region [65%]) reported using synthetic marijuana. Although synthetic marijuana use could not be verified by urinalysis, its use has been increasing rapidly, especially among teenagers and young adults based on survey data and drug seizures since 2013 [6]. According to a study of drug arrests between 2010 and 2014, the most commonly seized and used substances were cannabis, hashish (74.3%) and marijuana (15.2%), followed by synthetic marijuana (26.6%). Although synthetic marijuana has been mistakenly linked to cannabis, it is often easier to obtain, less expensive, and far more dangerous, causing more severe adverse health effects and dependence than cannabis [6]. In the West Bank, synthetic marijuana is mixed with tobacco and with other more toxic compounds including insecticides, rodenticides, and acetone to make it a more potent substance for a lower price [22].

Based on urinalysis, between 12.4% and 21.5% of HRDUs had methamphetamines in their system. The use of amphetamine-type stimulants (ATS), mainly amphetamines, methamphetamines and amphetamine analogues of the MDA-type, including MDMA or Ecstasy, is a growing global problem [23].

A comparison of reported drug use in the previous month with drugs detected in urine, other than marijuana and synthetic marijuana, showed differences in consistency by location. Descrepancies between reported use and the results of the urinalysis may be explained by ignorance of the type of drug used, and the interval of screening as many of the listed substances will not appear in urine after 2–4 days.

The combination of drugs found in this study can produce additive adverse effects on the respiratory and cardiovascular systems. Benzodiazepines and opioids, including heroin, morphine, methadone, codeine and Tramadol, all have central nervous system (CNS) depressant effects. Alcohol is another CNS depressant commonly used in combination with these drugs. Palestine is predominantly a Muslim country, and within Islam alcohol is forbidden (Haram) according to the Qu’ran. Yet, Palestinian law allows for its production and sale.

Amphetamines, cocaine and tricyclic anti-depressants are also associated with risks to the cardiovascular system, including hypertension, life-threatening arrhythmias, and circulatory collapse. Furthermore, the combination of cocaine with alcohol results in increased cardiotoxicity [24]. Studies found that the reason for combining drugs can be intentional for additive recreational effects or can be totally random and unintentional [25, 26]. Regardless of the reason behind it, polydrug use found among the study population is alarming and carries a high risk of additive side effects that could be fatal and can complicate medical interventions in case of toxicity as multiple agents and antidotes could be needed.

Our research found that older HRDUs from the West Bank and the Gaza Strip who were imprisoned were more likely to seek assistance for illicit drug use, which is in line with findings from a previous study conducted among Latinos [8]. This could be explained by use of the rehabilitation services at prison, which are mostly medical, or could also be explained by individuals seeking rehabilitation services to avoid going to prison again. In the West Bank and the Gaza Strip, suffering from the consequences of drug use, memory loss and withdrawal symptoms, respectively, was also associated with seeking rehabilitation services, which is in line with previous research [8], which is comparable to what we observe in the West Bank where individuals who have been imprisoned are more likely to seek such programs.

This study has several strengths. First, it is the first study in Palestine to estimate the extent of high-risk drug use in Palestine among males aged 15 and above, including the extent of polydrug use and the prevalence of ever injecting drugs. Our findings provide evidence to inform prevention and treatment services. Second, our data provide more granular insights into the extent of HRDU by sampling three distinct areas in the West Bank (North, middle, and south), as well as in Gaza. Third, this is the first study to examine factors associated with seeking rehabilitation services among HRDUs to inform policy. Fourth, drug use was verified based on urine analysis, rather than self-report.

However, a major limitation in this study is that females were not included. Females who use illicit drugs are known to be at higher risk than males due to the fact that females have more limited rehabilitation treatment options. Cultural expectations and constraints pose significant barriers to females taking part in any rehabilitation program. In addition, there are inadequate rehabilitation treatment services tailored to the special needs of females who use drugs and who are likely to be more vulnerable to sexual harassment and abuse. Although males who use illicit drugs certainly know females who use illicit drugs, female illicit drug users are normally more hidden and stigmatized than male illicit drug users in Palestine, as in other countries. Nevertheless, it is essential that female illicit drug users are at least qualitatively studied and that appropriate rehabilitation treatment services are available to them. Another potential bias may have been reporting bias due to culture and religion and heightened stigma towards drug and alcohol use. However, we took several precautions to ensure participants felt comfortable, including involving illicit drug users in the planning of the survey, collecting data anonymously, hiring former illicit drug users to screen participants, hiring recruiting trained data collectors, and providing a safe and accepting survey environment. Finally, as participants were not randomly selected, unknown confounders were not adjusted for in the study design. Although sampling begins with non-randomly selected seeds, which introduce a large amount of bias, a goal in RDS is to attain a sufficient number of waves whereby the sample transitions to convergence. Convergence is an indication that the final estimates are no longer impacted by the bias of the seeds and that the final estimates represent the network of the population sampled [15]. In our sample, we reached up to 14 waves and attained convergence on all key variables reported in this paper.