Small Wars Journal

Getting off: The Implications of Substance Abuse and Mental Health Issues Among Former ISIS Fighters for Counterterrorism and Deradicalization

Tue, 06/25/2019 - 11:33am

Getting off: The Implications of Substance Abuse and Mental Health Issues Among Former ISIS Fighters for Counterterrorism and Deradicalization

Daniel Koehler and Peter Popella


The so called “caliphate” of the terror organization “Islamic State” (IS, or: DAESH, ISIS, ISIL) has been defeated. When in March 2019 the last ISIS held territory was captured by the Syrian Democratic Forces (SDF) the group’s “terrorist semi-state” came to an end. This, however, does not mean that the group itself has been beaten. On the contrary, ISIS still very much presents a significant threat, as the recent mass casualty attacks on Sri Lanka demonstrate. The loss of physical territory and a narrative of victory will still likely damage the group’s appeal to recruits from around the world. At the same time, hundreds if not thousands of former IS fighters and other members, including many foreign nationals who joined the group for multiple reasons, are now awaiting an uncertain future in Kurdish or Iraqi detention. The exact number is unclear but in December 2018 Kurdish forces considered releasing some 3,200 ISIS prisoners (1,100 fighters and 2,080 family members). The United States has urged European nations to repatriate about 800 former IS fighters to prevent an uncontrolled infiltration of their territories. So far, only few European countries have declared to take back small numbers of IS fighters on a case by case basis, such as France for example, leaving the question of what to do with the “jihadists no one wants” wide open and heatedly debated. Few countries have begun to repatriate minor children and sometimes their mothers from Kurdish captivity, such as for example the U.S., Germany and France. But what about the men, who are almost surely former combatants? The options are quite limited: leave them where they are and let the Kurdish or Iraqi forces deal with them; process them one by one once they show up at an embassy or at home after they might have travelled back using unknown and oftentimes illegal means; or bring them back in a controlled and systematic way that includes collection of evidence for prosecution on the ground (e.g. collecting DNA samples, witness statements, documents from Kurdish forces). In any case, the assessment and mitigation of risks posed by those individuals is of key importance for the future stability of the region and the detainees’ home countries.

One essential aspect affecting individual risk is mental health, such as for example the role of Post-Traumatic Stress Disorder (PTSD), that has been found to significantly increase the threat posed by returning foreign fighters. Furthermore, as it happened throughout history when fighting forces were facing superior opponents and ultimate defeat on the battlefield during “final stands”, the use of drugs to enhance fanaticism, physical strength and to prevent fatigue, hunger, thirst and exhaustion was also reportedly present among IS’s fighters. The substance of choice for IS, Captagon or fenethylline, was so famous among the group’s fighters, that it was used even during terror attacks, for example in the November 2015 Paris attacks. So far, however, the effects of long term Captagon abuse on mental health and thereby on the potential risk posed by returning foreign fighters has not been discussed. The following article gives a first assessment on the role of substance abuse for counter-terrorism, deradicalization and risk mitigation related to returning IS fighters.   

A Short History of Substance Abuse in Wartime

Before turning our focus to the specifics of IS’ Captagon usage and its consequences for dealing with returned fighters, it is necessary to recognize the historical context of substance abuse in wartime. As the seminal study “Shooting Up. A Short History of Drugs and War” (Oxford University Press, 2016) by Lukasz Kamienski has shown, drug use in warfare goes back as far as historic accounts of war itself. Even Homer’s descriptions of ancient Greek warriors included stories of drinking wine before battle and of course many armies in history have resorted to alcohol in order to assure bravery and high spirits of their soldiers. Morphine was used widely in the American Civil War and Cocaine in World War I. In the following World War II, the Nazis started to supply their soldiers with amphetamines, more specifically with a drug called Pervitin (an early version of crystal meth). The Allies countered with Benzedrine, which was also widely distributed and used at the time. When the development of military technology and tactics evolved, so did the drugs accompanying the forces fighting with them. The Vietnam War became widely known for the devastating long term effects of authorized use of dextroamphetamine, which was still in use in the 1991 Gulf War. Today, the U.S. Army is officially the only military in the world allowing for controlled pharmacology-assisted fatigue management with an eugoric called modafinil (Provigil) but the Chinese and Russian militaries have been known to produce equal substances as well.

Taking drugs during wartime may serve some obvious purposes but might also happen for some reasons not immediately clear to the observer. First and foremost, enhancing performance (e.g. staying awake longer, remaining alert, being less hungry and thirsty, having more energy and combat aggressiveness, experiencing less fear), dealing with combat stress, as well as treating injuries and pain are the most important drivers behind drug use on the battlefield. However, social bonding (getting high together) and dealing with boredom are also known reasons.

What is Captagon?

Captagon responds to the chemical compound fenethylline (C18H23N5O2) and is also known under its Arabic street names Abu Hilalain or Al-Kaptagon or its IUPAC name (R,S)-1,3-dimehtyl-7-[2-(1-phenylpropan-2-ylamino)ethyl]purine-2,6-dione. Fenethylline is a solid substance and the easiest way of administration is orally by ingesting a tablet. However, it can also be given intravenously or as subcutaneous injection. Fenethylline acts as a strong stimulant of the symphatic nervous system, activating the body’s “fight-or-flight” response. Users are thus more awake, euphoric, possess a low aggression threshold, are physically stronger and feel less pain – characteristics warmly welcomed in violent confrontations. They also feel less hunger and bowl movements as well as urination urges are decreased. Fenethylline is a prodrug, meaning that is metabolized by the human body into two pharmacological active substances: amphetamine and theophylline. While amphetamine is well known by partygoers under the synonym speed or pepp, theophylline is used for treating pulmonary diseases like asthma or chronic obstructive pulmonary diseases (COPD). Remarkably, the combination of both compounds is thought to be advantageous for the user in ways beyond the activity of the single compounds: 1) they act synergistically, amplifying the psychoactive effect, 2) fenethylline is taken up into the central nervous system faster than either drug alone, 3) the vasodilating effect of theophylline counteracts increased blood pressure caused by amphetamine and 4) fenethylline is less addictive than amphetamine itself, due to the lower accumulation of fenethylline-derived amphetamine in the brain. However, Captagon is still an addicting compound.


Fenethylline was invented in 1961 by the German pharmaceutics company Degussa AG in 1961 as an alternative to amphetamine for treatment of hyperactivity (Attention Deficit Hyperactivity Disorder), as well as narcolepsy and depression. After widespread use for around 25 years it was banned in most countries after the World Health Organization listed it for international scheduling under the Convention on Psychotropic Substances in 1986 due to side effects like emotional detachment and sleeplessness. Originally, production as an illegal narcotic was located in the Balkans with the main consumer market for the recreational drug Captagon located in the Middle East. The substance became so widely used that in 2017 it was the most popular narcotic on the Arabian peninsula. It has been estimated that 40% of drug users between ages 12-22 in Saudi Arabia and that three out of four patients treated for drug problems in the country are addicted to fenethylline, almost exclusively in the form of Captagon.

With the outbreak of the Syrian civil war in 2011, Captagon production moved closer to its consumer base and provided several Syrian rebel factions with an opportunity to finance their armed struggle against the Assad regime. Organized crime activities for fundraising the rebellion (producing and selling counterfeit Captagon on the black market) mixed with the ancient wartime tradition to supply fighters with performance enhancing substances. In the process the drug’s recipe might have been altered and its effects significantly increased, as some scientists have suggested. However, even though the production hub in southeast Europe attempted a comeback in 2017, Captagon had by then already been dubbed the “jihadi drug”. The various opposition groups in the Syrian civil war learned to appreciate the increased alertness, strength, wiped out fear and ravaging courage among their fighters, when they took the drug themselves. Some reports from the battlefields in Syria even claim that “people take so much, if you shoot them, they won’t drop.”

Effects of Captagon Abuse

The side effects of Captagon abuse are similar to those of amphetamines. Specifically, visual distortions, hallucinations, acute heart failure, acute myocardial infarction (AMI) and epileptic fits have been associated with prolonged use of fenethylline. But these are not even the worst consequences. Extreme depression, lethargy, sleep deprivation, mood swings, confusion, feelings of anger or rage, irritability, impatience and psychoses (featuring paranoid delusions, agitation, aggressiveness) can be caused by long-term use. Furthermore, long-term amphetamine abuse is strongly associated with significant cognitive impairments, such as loss of short term memory and decreased attention spans. Amphetamine does not create a physical but psychological addiction. One has to bear in mind though, that counterfeit versions of Captagon are known to use all sorts of other chemicals oftentimes of low quality. Sometimes, cheap and homemade Captagon does not even include fenethylline. These other substances (e.g. plain amphetamine, ephedrine, caffeine, acetaminophen) come with their own list of severe side-effects, not to speak of those created by combining them.

Determining the root causes of psychotic symptoms (e.g. PTSD, substance abuse, primary psychotic illness or other) is highly difficult. Looking at amphetamine users in general, up to 46% will develop psychotic symptoms such as delusions, paranoia or hallucinations and for many of those individuals these side effects will continue even more than one month after the last substance consumption. This means that urine tests for example might become useless in the search for the cause of the psychosis. In addition, the symptoms described in various case studies overlap with acute schizophrenia spectrum psychosis. An adequate diagnosis and treatment therefore require the detailed history of the psychotic symptoms and drug use, collection of collateral information, careful physical and mental status examinations, and familiarity with cultural factors – most of which of course is not available to treatment providers when it comes to returned foreign fighters. This group of potential psychological and psychiatric patients also displays additional risk factors that could significantly impact the overall danger of these Captagon side effects, such as combat training and experience, traumatic events, religious fanaticism, terrorist indoctrination, brutalization on the battlefield or through normal life practices in IS’ caliphate (e.g. public executions) and the development of other mental health issues through participation in violent extremist and terrorist groups and their ideologies. Substance abuse induced mental health issues or psychoses might interact with suggested personality traits and mindset features of violent extremists, such as  perceptions of a crisis involving violations of posited sacred values (which could interact with paranoia) and justifications for the use of violence (which could interact with Captagon induced anger, aggressiveness or rage). In short, Captagon abuse effects and the specific features of membership in violent extremist and terrorist milieus might create a highly dangerous mixture of mental health issues on top of those effects usually associated with battlefield experiences (such as PTSD) or other potentially pre-existing mental health illnesses (e.g. Autism Spectrum Disorder (ASD)).      

Consequences for Counterterrorism and Countering Violent Extremism/Deradicalization

The usual consequences of substance abuse for counterterrorism are of tactical nature. Observers have noted the potentially altered behavior of drugged jihadist fighters encountered on the battlefield or during terror attacks: “stand-offs and sieges against such groups may last longer if the fighters are on drugs such as Captagon. (…) On the other hand, the physiological symptoms of drug withdrawal in violent non-state actors have led to the outbreaks of violence. (…) Withdrawal symptoms can last from a few days in the cases of cocaine and heroin to a few months in the case of methamphetamine, thus varying the length and severity of unpredictable behavior.” In addition to general unpredictability and irrational behavior during combat and terror attacks, post-conflict or post-detention scenarios might also be severely impacted through previous substance abuse. Detainees suffering from withdrawal symptoms or psychoses automatically pose a different threat and burden to security forces handling them. Special needs for supervision, initial treatment, separation from other detainees or even solitary confinement create additional strains on resources of any force tasked with processing and guarding such detainees. Apart from managing risks and threats posed by drugged detainees or those suffering from withdrawal symptoms, access to medical assistance for the sick and wounded, whether they have been engaged in active combat or not, is guaranteed through various international agreements, including the Geneva Convention, International Humanitarian Law (IHL) and International Human Rights (IHR). Naturally, physical injuries and primary needs of detained combatants (e.g. food, water and shelter) are prioritized, if resources, time and tactical situation allow for the provision of these basic services. Mental health issues such as psychoses or severe withdrawal symptoms are likely to be dismissed and left for long-term aftercare, if at all.

It is therefore likely that former IS fighters who return to their home countries have not received anti-toxication or mental health treatment. On the contrary, it is to be expected that additional substances might have been consumed to cope with detention and that the alarming conditions of Kurdish (and other) POW camps (e.g. overcrowding, violence between detainees, lack of basic supplies) have significantly contributed to an overall worsening of mental health amongst the detainee population, especially for those already suffering from pre-detention and substance induced psychoses. Without information regarding the returned fighters’ medical history, previous substance abuse, symptoms of mental health issues or even professional judgments for example by a detention camp doctor, identifying and appropriately treating patients will become extraordinarily difficult. While Western countries usually provide statutory access to medical and mental health services for prisoners and typically involve the option of psychiatric or psychological assessments as part of the trial and sentencing process, this might come too late. Most countries, at least currently, treat the issue of returning foreign terrorist fighters as a “bridge to be crossed once we get there”-kind of problem. There is (almost) no attempt to systematically gather and return fighters by the nations of their citizenship in combination with the collection of criminal evidence admissible in a court of law and other relevant information to help with risk mitigation (such as for example medical histories). Of course, those individuals displaying acute psychotic symptoms will be immediately recognized as suffering from mental health issues and likely to be transferred to psychiatric facilities if they make it back to their home countries. Other, more subtle or periodic outbreaks of mental health issues might not be identified for a long time, which also could be complicated through prolonged investigative custody and criminal justice proceedings.

Substance abuse and mental health issues also present significant challenges for deradicalization, exit or reintegration work, which has become a cornerstone of international and national counterterrorism efforts. For example, the United Nations Security Council (UNSC) Resolution 2178 from 2014 urges all member states to establish effective rehabilitation measures for returned fighters from Syria and Iraq. As many countries have accordingly established such rehabilitation initiatives, the question of the specific challenges posed by program participants suffering from mental health and substance abuse issues has for example been noted by the European Union’s “Radicalisation Awareness Network (RAN)”, which sees this group of potential recipients of deradicalization measures as “multi-problem target group”. Mental health issues and effects of substance abuse might slow or even hinder a reintegration and deradicalization process, especially through irrational, paranoid and uncooperative behavior. Deradicalization programs also usually lack psychological or psychiatric capabilities or the resources to provide such services through external partners. In addition, specialized treatment facilities in many countries operate on long waiting lists and terror suspects or convicts are likely to be placed on lower priority due to the considerable stigma attached to them. As pointed out in the RAN working paper “Multi-problem target group: the influence of mental health disorders and substance abuse on Exit work”, the exit process from a violent extremist environment holds its own psychological challenges, such as fear, hopelessness, guilt, shame, anxiety or depression. Such potential effects of a deradicalization process could trigger or enforce previous mental health issues and substance abuse. On top of this come legal barriers against coordination and information sharing between deradicalization and mental health professionals, such as data protection and privacy legislation.

Luckily, most serious deradicalization programs around the world now include psychologists as a standard part of multi-agency approaches. This was explicitly recommended by the “Rome Memorandum on Good Practices for Rehabilitation and Reintegration of Violent Extremist Offenders” for example, in which it is stated that “psychologists can play a key role in the rehabilitation process and could be fully integrated into these programs”. “Additional Guidance on the Role of Psychologists/Psychology in Rehabilitation Programmes” were developed by the International Centre for Counter-Terrorism in The Hague (ICCT) together with the countering violent extremism network Hedayah. This gives an indication of the importance placed on psychologist and other mental health professionals within countering violent extremism and deradicalization work. However, this still falls short of adequate access to necessary medication or psychiatric treatment in specialized and dedicated facilities. Only very few deradicalization programs possess the resources needed for such a full bandwidth of services, such as for example the Saudi Arabian program. In most Western countries that operate deradicalization programs, working level collaborations between mentors and psychiatric as well as psychological treatment providers have been formed on a case by case basis. Nevertheless, attempts to institutionalize this form of cooperation like the German expert network on extremism and psychology (“Fachstelle für Extremismus und Psychologie”) are essential steps into the right direction to create a constant exchange between mental health and deradicalization experts.      

A specific spoiler for a successful reintegration and deradicalization processes related to the mental health and substance abuse question could also be the “crime-terror-nexus”. Returned fighters with or without substance addiction, contacts to manufacturing and distribution networks, as well as knowledge about the production process of counterfeit drugs like Captagon, weapons training and combat experience could be very attractive recruits for organized crime syndicates. There is no reason why returned fighters could not easily form new alliances with drug cartels or criminal organizations based on drug production and distribution, which could be mutually beneficial for both sides, something which IS has already done as part of funding its “caliphate”.  

Conclusions and Recommendations

Summing up, mental health issues induced through abuse of Captagon and other substances could be significant additional risk factors increasing the threat posed by returning foreign terrorist fighters. Those increased threats and challenges not only affect classical counterterrorism and detention management but also rehabilitation and deradicalization efforts. A third variable in the equation is the potential effect on the “crime terror nexus” that directly influences the role played by substance abuse among returned IS fighters and criminal external networks spoiling the risk mitigation process. The good news is that if patients stopped taking Captagon, some of the side effects improved rapidly and that withdrawal symptoms are rarely observed. Unfortunately, getting to the point of a controlled and save withdrawal without the option of substituting Captagon with other drugs and with mental health care ready to accompany the process will be much more difficult. Mental health issues and substance abuse are but one of many complex and high-risk factors involved in handling returned foreign terrorist fighters, but they arguably belong to the most important ones. Without any predictable behavior and a healthy mind able to process and reflect upon outsider intervention (ranging from prison, deradicalization to death) most tools at the disposal of counterterrorism (including rehabilitation) will be close to useless. Untreated returned fighters with severe mental health issues and substance addiction will inevitably become high threat cases for law enforcement, either within the realm of terrorist or other criminal violence.

Based on this brief overview of the challenges for counterterrorism and deradicalization surrounding mental health and substance abuse among former IS fighters, some key recommendations for policy makers and front-line practitioners including law enforcement and prison management can be provided:

  • An initial standardized psychological or psychiatric screening as part of the intake procedure for returned IS fighters must be conducted.
  • Strong collaborations between deradicalization programs and mental health professionals must be established and institutionalized.
  • Training to recognize basic mental health issues and appropriate first line responses should be provided to all personnel in direct contact with returned or detained foreign terrorist fighters.
  • Psychologists or psychiatrists should be standard members of multi-agency teams processing foreign terrorist fighters, either on the law enforcement, prison, probation or deradicalization side.
  • Specialized training in the basics of the psychology of radicalization and deradicalization, as well as the specific contents of IS’ ideology should be provided to mental health professionals tasked with handling foreign terrorist fighters.
  • More research on the effects of mental health issues on deradicalization processes must be financed and conducted.
  • More psychiatric and psychological treatment space for high risk terrorist offenders must be financed and provided, given the overall goal of risk mitigation and the prevention of future violence.
  • Law enforcement and intelligence work must expand the focus on potential links between organized crime (especially drug cartels and syndicates) and terrorists. Most of the focus currently looks at the criminal pasts of terrorists (with the aim of detecting violent radicalization processes in the criminal space) and fundraising activities of terrorist organizations using traditional organized crime (e.g. trafficking weapons, drugs, humans). The potential risk of former IS fighters (re-)joining organized criminal enterprises while maybe retaining their extremist ideology and networks could create a new dynamic within the phenomenon often dubbed “narcoterrorism”.

About the Author(s)

Dr. Peter Popella is a scholar of microbiology and specialist for infectious bacteria and antibiotic resistances. He holds a B.Sc., M.Sc. and Ph.D. degree from the Eberhard Karls University Tuebingen, Germany. Until 2018 he was working at the ‘Interfaculty Institute of Microbiology and Infection Medicine Tuebingen’. Currently, Peter is an independent researcher interested in infection biology, biological and chemical warfare and terrorism.

Dr. Daniel Koehler (Twitter: @GIRD_S) is a Fellow at George Washington University’s Program on Extremism, Editorial Board Member of the International Centre for Counter-Terrorism (ICCT) in The Hague and Founding Director of the German Institute on Radicalization and De-Radicalization Studies (GIRDS). He is also the Co-Editor in Chief of the peer reviewed JD Journal on Deradicalization. He is an expert in right-wing terrorism and de-radicalization and recently published standard works in both fields. He studied religion, political science, economics, as well as peace and security studies at Princeton University, Free University Berlin and the University of Hamburg.



Fri, 12/24/2021 - 7:38pm

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Tue, 09/28/2021 - 8:10am

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