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Exploring e-psychonauts perspectives towards cocaine effects and toxicity

Abstract

Background

According to the World Drug Report, cocaine is the second most used drug globally after cannabis. Online discussion forums enable the understanding of authentic drug users’ experience as it is anonymous. Therefore, this study determined the uses, effects and toxicity of cocaine from the perspectives’ of e-psychonauts.

Methods

A qualitative study was conducted using six popular discussion forums. From these discussion forums, 1229 posts from 50 threads were subject to thematic analysis. Hence, the information from these threads were examined carefully for patterns and codes among the data. The codes were then collated into subthemes and themes.

Results

The four main themes emerging from the study were related to cocaine characteristics and use, e-psychonauts’ knowledge and experience, desired effects and adverse events. The main characteristic associated with cocaine use was purity that was highest in the US being nearest to the source. The most common cutting agent encountered in cocaine samples was levamisole that increased the chances of immunosuppression and cardiovascular toxicity. Purity depended on the source of purchase that included street dealers, dark web and surface web. Hence, e-psychonauts recommended purchase of cocaine from known dealers rather than websites with unknown sources. E-psychonauts mainly used cocaine in social context and parties or to self-medicate against anxiety and depression. Effects desired from cocaine use were mainly euphoria and increased energy. However, tachycardia and myocardial infarction were the main adverse events. It is noteworthy to mention that myocardial infarction was idiosyncratic and was often lethal. Myocardial infarction was more often reported when cocaine was combined with alcohol due to the production of cocaethylene. Social harm was also reported as a consequence for the use of cocaine that resulted in homelessness and broken relationships.

Conclusion

Online discussion forums allowed the understanding of e-psychonauts’ experience with cocaine use. Not only it informed about the sources and modalities of use of cocaine but also about the adverse events and social harm associated with cocaine use. The present findings serve as useful information for practitioners and healthcare professionals dealing with cocaine users.

Background

According to the United Nations Office of Drugs and Crime (UNODC) World Drug Report (2021), cocaine is the second most used drug worldwide after cannabis [1]. The latter report stated that in 2019, 20 million people used cocaine and that corresponded to about 0.4% of the global population [1]. The latter figure rose by 24% in only 10 years-time where cocaine overdose cases had increased from 3822 in 1999 to 15,883 in 2019 [2, 3]. This latter figure did not decrease with the Covid-19 pandemic that in turns contributed to increase in drug use worldwide. In this respect, increase in cocaine-related seizures was seen worldwide and increase in shipment sizes was featured [4,5,6]. Cocaine is seen as a moderately accepted drugs in comparison to cannabis and heroine [7]; where cannabis is seen as safe and heroine is seen as highly toxic drug [7].

The impact of cocaine use/abuse results in adverse drug events (ADEs) and lethal effects where it is the most frequently encountered drug in drug-related deaths [8]. ADEs linked to cocaine use were reported for multiple organs including nervous, respiratory, cardiovascular, gastrointestinal, kidneys and liver [9, 10]. Nonetheless, the majority of reported research related to effects/toxicity of cocaine included pharmacological/toxicological studies [11, 12] with limited studies analysing perspectives and experiences of users/abusers [13, 14]. The latter four studies explored the culture and context of cocaine use with limited information on experience of users in terms of specific effects. This is partly due to drug use (cocaine in this case) is a sensitive topic and subjects users to ‘blame’ and ‘judgement’ when discussing it. Online discussion forums serve as a popular platform for drug users (including e-psychonauts) to share their experiences, thoughts and views in a blame free environment [15, 16]. Thus, posting on online discussion forums is anonymous where it does not require users to share their username, age, gender, location and/or identifiable information. Particularly in cases of illicit drugs such as cocaine, drug use on online discussion forums could be discussed without fear of repercussions [17, 18].

Previous drug-related research has utilised online discussion forums’ to explore users’ perspectives towards new psychoactive substances (NPS) [19,20,21]. However, none of the aforementioned studies explored cocaine use and the only study regarding cocaine use from web-based information did not involve online discussion forums [22]. Subsequently, it was important to study cocaine use from online discussion forums especially that cocaine use has increased since the COVID-19 epidemic started where people’s mental health and psychiatric well-being deteriorated [23, 24].

Therefore, this study aimed at understanding the uses, effects and toxicity of cocaine from the perspectives of e-psychonauts via online discussion forums. Subsequently this study complemented the previous studies by providing in-depth insight into cocaine use considering its sourcing, different trends in use within diverse context, effects sought and toxicity experienced. By analysing online discussion forums, this study was able to provide authentic experience that had been expressed by users’ in a blame free environment. Furthermore, in-depth qualitative analysis enabled to understand whether early users endorse the use of cocaine or discourage it.

Methods

Data collection

A qualitative study was conducted regarding users’ experience of cocaine from online discussion forums. Data was acquired from six main discussion forums previously identified by the Psychonaut Web Mapping Project: bluelight.org, drugabuse.com, drugs-forum.com, erowid.org, hipforums.com and partyvibe.com [25]. Initial forums inspection yielded 7959 threads of which 50 threads (containing 1229 posts) were found relevant. Inclusion criteria comprised threads that outlined experiences, characteristics, motivations and effects surrounding cocaine use. Exclusion criteria comprised threads containing general scientific information not relating to users’ perspectives. All collected posts were in English language and were in the period ranging between 17th of December 2020 and 3rd of February 2021. Threads were saved as PDF documents on the access date in order to preserve information on the documents (Table 1).

Table 1 Details of threads included in the study

Participants

The 1229 posts were informed by 236 individuals of which 131 disclosed their age, 40 disclosed their sex and 178 disclosed their geographical location (Table 2). In this respect, the median age reported was 32 years old, 34 were males and six were females. Where location was reported, 21 countries were mentioned of which the US, UK and Canada represented the majority (Fig. 1).

Table 2 Characteristics of e-psychonauts (n = 236) from online discussion forums
Fig. 1
figure 1

Reported geographical location of e-psychonauts

Ethical considerations

The study was conducted according with the ethical standards laid down in the 1964 declaration of Helsinki and its later amendments. Ethical checklist obtained from Liverpool John Moores University was completed where the study was qualified as no risk. No ethical approval was required as information collected in this study was already in the public domain [26]. Nonetheless, anonymity was ensured in all threads where each thread was given a number and any users’ data that indicated identity/nicknames were removed. Considering that the presence of a researcher influences participants in qualitative studies [27], no contributions to the posts were made and no data were shared outside the study.

List of definitions

An adverse drug event (ADE) is an incident associated with the use of a drug but not necessarily causally related [28]. A drug overdose, also known as acute poisoning, occurs when a user takes a high dose of a drug whether accidentally or intentionally and results in serious, harmful or lethal consequences [29]. Toxicity is defined as the “degree to which a substance can harm humans or animals” [30]. A drug-drug interaction is defined as “an action of a drug on the effectiveness or toxicity of another drug” [31]. Polydrug use is defined as the administration of two or more drugs [32]. Psychonauts are individuals who take drugs for the exploration and experience [33]. The ICD-11 classification for different conditions is listed in Appendix 1 [34].

Data analysis

The PDF documents were exported to NVivo Pro 12 where content analysis was applied and that allowed to explore patterns and themes among the posts [35,36,37]. The standards for reporting qualitative research (SRQR) were applied (Appendix 2). In this sense, data in threads were read carefully by two investigators (AK and SA) in order to minimise bias. In this sense, each thread was read line-by-line thoroughly where relevant sections were highlighted and codes were assigned accordingly. No limit was placed on the amount of text that could be coded in one code where the text could range from a single word to a whole paragraph. Quotes were grammatically corrected without impairing the integrity and subject of the quote so the quotes could be read easily. Some quotes also were coded numerous times if different information were provided in the same quote. Then the codes were read and re-read and collated into subthemes that encompassed four overarching themes related to: cocaine characteristics, users’ knowledge and experience, desired effects and ADE. Figure 2 shows the coding procedure. The threads that had already been coded were re-read for comments relating to the overarching themes in order to ensure nothing have been previously missed. Then, saturation was reached where no new themes emerged from the text and that indicated the end point for the study. The codes were entered into summary tables for each subtheme.

Fig. 2
figure 2

Coding procedure for quotations obtained from online discussion forums

Data validation

The inter-rater reliability of the threads was assessed by postulating the threads to a third researcher (AA). High level of agreement was achieved with inter-rater reliability of 95% was obtained. The information within threads were validated by matching the findings from clinical reviews regarding cocaine and that authenticated the accuracy and credibility of the findings [8,9,10, 38].

Results

The analysis of the online discussion forums in relation to cocaine resulted in 50 threads with 1229 posts. Of these posts 748 quotations were coded (Table 3). The aforementioned threads encompassed four themes: Cocaine characteristics and use, users’ knowledge and experience, desired effects and toxicity and ADEs.

Table 3 Themes, subthemes and example quotations extracted in the study

Cocaine characteristics and use

Analysis of threads showed five main sub-themes as part of cocaine characteristics that were related to purity (n = 81), purchase (n = 14), prices (n = 31), administration (n = 83), drugs alternatives to cocaine (n = 9) and polydrug use (n = 13).

Purity of cocaine reported had a wide range of variability between 10 and 60% and that depended on the country of purchase. Highest purity was around 70% and was reported in South American countries being Bolivia, Colombia and Peru. This was followed by Florida that was close to the aforementioned countries. Purity of cocaine encountered in Europe was in the range of 30–60%. 30% purity was seen in the UK whereas 60% for Belgium, France and Netherlands (60%). E-psychonauts checked for purity by either checking the melting point of cocaine or sending it for testing. Moreover, e-psychonauts associated lower grade cocaine with lower levels of euphoria and higher levels of ADEs being: anxiety, nose irritation, bleeding and paranoia. The aforementioned ADEs  were attributed to cutting agents used. Hence, increased stimulation, anxiety and paranoia was related to cocaine cut with Adderall, amfetamine, methamfetamine, aspirin, caffeine and/or methamfetamine. Methamfetamine/cocaine combination was further reported as highly addictive. Moreover, increased numbness was observed when cocaine was cut by benzocaine, lidocaine, procaine and/or cathinones. Cocaine cut by levamisole caused immunosuppressant effects, nasal infection and cardiovascular damage. Lethal effects were stated regarding cocaine cut by fentanyl. Of the aforementioned mentioned impurities, levamisole was the most frequent reported cutting agent:

‘Levamisole has increasingly been used as a cutting agent in cocaine sold around the globe with the highest incidence being in the USA. In 2008–2009, levamisole was found in 69% of cocaine samples seized by the Drug Enforcement Administration (DEA) (QN167).’

Though users cited statistics decade ago, other users reports levamisole still the main cutting agent in recent years. For instance, one user reported:

‘It’s something like 90% of coke has levamisole in it… Not really any sort of test serves as purity, especially with levamisole being cut into the vast these days (QN165 and QN168).’

Additional cutting agents reported were baking soda, gamma-butyrolactone (GBL), ephedrine, hexedrone, lactose, milk powder and Ritalin.

Regarding purchase sources and pricing, sources included the dark web and surface web sources as well as street dealers. Price was only reported by few years and was witnessed as increasing by two folds over the last 2 years in the US and the UK. Where reported, the price for cocaine was between £40–60 (per 1 g) in the UK and $80 (per 1 g) in the US.

Route of administration of cocaine included mainly snorting followed by chewing, IV injection parachuting and smoking. Snorting of cocaine was done on its own or alongside consumption of alcohol synchronously or intermittently. Effects after snorting were reported as long-lasting for days and potentially resulting in overdosing. Effects attained from snorting comprised numbness in nose/sore throat and euphoria. Nevertheless, snorting was associated with nasal bleeding, severe dehydration, high blood pressure, cardiac damage, and damage to nose and face. Where damage occurred to nose and face, IV was the second sought route for cocaine intake. IV was described as the fastest route (100% bioavailability) but extremely dangerous causing dehydration, violent seizures, involuntary muscle movement and death. Smoking (crack) through roll ups, pipes or inhalers was the least favourite route due to its short half-life and association with chronic hallucinations. Cocaine was also orally administered; however, oral route was slower route with long lasting effects when compared to other routes of administration. Oral routes involved drinking cocaine in drinks, parachuting cocaine and/or chewing coca leaves.

Drugs alternative to cocaine encountered included amfetamines, cathinones, methylene dioxide methamfetamine (MDMA), methyl phenidate and n-ethyl pentedrone. Reasons behind choice of the aforementioned drugs included price, stimulant effects and duration of effects. One user reported:

‘Cocaine is both highly euphoric and, to a degree, subtle. If you have been doing cathinones (for example) you may be expecting a twice-strong half-fun experience’. (QN203).

Polydrug use encompassed the use of cocaine alongside other drugs such as: heroin, marijuana, alcohol, stimulants and benzodiazepines. Polydrug use were sought to alter the effects of cocaine where the interaction could to increased or decreased stimulant effects. Cocaine-heroin combination (crack and smack) was taken in order to achieve more intense and longer lasting effects that using cocaine alone. Where stated, users mixed around 2.5–3 g of cocaine with around 1 g of heroin over the course of 24 h yet described the effects as ‘out of control’, ‘hitting the nail on the head’ and/or ‘trouble’.

Marijuana-cocaine combination were taken either by smoking the combination when using primo cigarettes that comprised cocaine-laced marijuana cigarettes, or by smoking marijuana cigarettes alongside snorting cocaine lines. The combinations was reported as bringing ‘strong body high vibes’, ‘instant alertness’ and ‘increased alertness’. However, the combination was described at other instances as ‘disappointing that the users felt no euphoria’. When combined with alcohol, users’ reported ‘heavily elevated high’ feeling, ‘high vibes’ and increased surge to drink. This could be attributed to the cocaethylene that in turns resulted in many unwanted effects related to the inhibitory effects of alcohol. Negative effects experienced related to cocaethylene were cardiovascular toxicity (unspecified), increased risk of overdose and increased risk of sudden death. Moreover, cocaethylene was stated to have longer duration of action that benzylecgonine (metabolite of cocaine) and was more potent that benzylecgonine. The duration of action reported for cocaethylene was 144 min compared to 60 min for benzylecgonine.

Users sought using cocaine with stimulants in order to achieve increased energy boost. Yet, cocaine-stimulants interaction resulted in nervousness, increased heart rate and paranoia. Specifically when taken with amfetamine and MDMA, users’ experienced worse come down in terms of anxiety, panic attacks, paranoia and nervousness. Anxiety resulting from cocaine-amfetamine combination was attributed to increased thoughts among users and increased their liability to overdose. Users described themselves as ‘close to death’ during panic attached.

The aforementioned effects were especially encountered during come down and did not get resolved even if depressants (such as benzodiazepines) were taken during come down. For instance cocaine-benzodiazepine interaction resulted in increased risk of OD and addiction to benzodiazepines. Yet some users still recommended to take alprazolam (Xanax) 0.5 mg half-way through the trip.

Users’ knowledge and experience

Three main subthemes emerged under e-psychonauts’ knowledge and experience relating to reasons for use (n = 47), self-medication with cocaine (n = 3), self-medication to control cocaine come down (n = 33) as well overcoming cocaine related ADEs (n = 7), and measures to quit cocaine (n = 17).

Cocaine was mainly used in social context including parties, music festivals and other events. Other reasons for using cocaine encompassed influence by educational colleagues, drug tourism, self-medication and/or as alternative to other drugs. In this context, cocaine provided relaxation, antidepressant effects, relief from cluster headaches and occipital neuralgia. Cocaine was preferred to alcohol, cannabis, ecstasy, methamfetamine and methylphenidate due to increased duration of action and decreased toxicity. E-psychonauts recommended limiting cocaine use to special occasions:

‘If at all possible, I would just try and limit your use to special occasions or maybe just be a weekend warrior (even that is quite taxing on the body/mind’ (QN305).

E-psychonauts also self-medicated with cocaine or with other drugs in order to avoid cocaine ADEs and/or comedown. Self-medication with cocaine was pursued in order to achieve anaesthesia, control depression, social anxiety and insecurity. However, these effects were described as short term:

‘Cocaine will fix some common problems such as boredom, depression, social anxiety, etc… But only in the very short-term, it’s not a very functional stimulant either since it lasts so little’. (QN272).

On the contrary, self-medication against cocaine ADEs included taking benzodiazepines or ketamine for anxiety. Benzodiazepines were the main recommended to take during comedown where the most common two derivative mentioned were alprazolam and diazepam. Ketamine, quetiapine and alcohol were also mentioned; yet, alcohol was warned against as it increased the chance of cardiovascular ADEs.

Desired effects

Users sought mainly stimulant effects when using coca leaves or cocaine. Coca leaves provided users with milder longer lasting stimulant effects in contrary to cocaine powder.

Desired effects were euphoria (n = 25), increased energy (n = 5), alertness (n = 1), increased confidence (n = 2), enhanced focus (n = 2), overcoming depression (n = 5) and inducing sexual arousal (n = 8). Euphoria was described as a ‘subtle buzz’ but could be ‘strong’, ‘massive’ and/or ‘overwhelming’ and enabled users to overcome boredom, depression and social anxiety:

‘For most people, cocaine isn’t really just a sense of ‘well-being’, it’s a very noticeable and powerful rush of dopamine that induces pretty strong euphoria’. (QN352).

Users recommended stopping snorting if the euphoria had not been achieved after the first few lines. Euphoric levels were related to purity of cocaine and it was found to be followed by feelings of anxiety and physical discomfort.

In social scenarios, cocaine increased confidence and increased ability to talk. Increased sociability and confidence lasted 30–40 min after snorting and enhanced focus enabled the completion of tasks but was dose dependant.

In order to overcome depression, users took cocaine to achieve a calming effect and escape reality and real-world problems however, e-psychonauts knew that cocaine did not fully solve their problems:

‘Cocaine will fix some common problems such as boredom, depression, social anxiety, etc… But only in the very short-term, it’s not a very functional stimulant either since it lasts so little’ (QN341).

Sexual arousal was also reported among users who experienced increased arousal and desire for intercourse. Sexual thoughts were reported as impulsive and disruptive to users’ lives.

Toxicity and adverse events

Toxicity and ADEs  reported by users comprised nervous system (n = 174), cardiovascular (CV) (n = 60), ear, nasal and throat damage (n = 24), cocaine-drug interactions (n = 68), lethal events (n = 10) and social harm (n = 17).

Nervous system ADEs

Toxicity relating to the nervous system included addiction, anxiety, paranoia, nausea, psychosis and seizures. Addiction was the most prevalent ADE and was described as difficult to hide, life ruining and leads to social harm:

‘It happens when someone takes too much of it. For many, this is a daunting task because it can be very addictive. The rush that people get from cocaine causes them to repeatedly take it. This is how the addiction to cocaine is formed. Sadly, an addiction to cocaine is scary because it can very much damage a person’s life. The high from the cocaine causes the user to not worry about it because they feel great at that moment. Cocaine is truly a dangerous drug’. (QN553).

Moreover, withdrawal symptoms lasted around a month and were restlessness, irritability and anxiety.

Anxiety was mainly experienced during night-time where users had dry mouth, clenched teeth, nausea, vomiting and difficulty breathing. Anxiety attacks were experienced within the first two lines of cocaine and increased proneness to overdose. For some users overdosing exacerbated the effects of anxiety attacks with experiences described as ‘close to death’. Panic attacks were reported alongside anxiety and in some instances were seen at a rate of one per day and led to hospitalisation. Paranoia was also experienced with anxiety when moderate to high doses of cocaine were used and was characterised by shaking, sweating and increased heart rate. Paranoia was found to be experienced outside of the home and in places where the user felt less comfortable. In some situations, paranoia caused users to hear noises outside or felt like they were being followed by the police or neighbours which led them becoming irritable. E-psychonauts further reported having seizures due to cocaine and encouraged users who had this experience to quit usage. Losing consciousness and death were found to be caused when seizures occurred to lone users.

CV ADEs

CV ADEs experienced by e-psychonauts were experienced even at low doses and encompassed increased blood pressure, arrythmia, tachycardia, myocardial infarction, stroke and sudden cardiac death syndrome. Tachycardia was experienced after the first line of cocaine and users felt their heart was ‘pounding‘. Other users experienced rapid heart beating before intermittently slowing down every 4-5 seconds. Overstimulation of the heart tissue from cocaine abuse caused myocardial infarction and strokes. Combination with alcohol exacerbated these effects and depended on users’ lifestyle, age and/or gender. Sudden cardiac death syndrome entailed the heart stopping its function acutely and unexpectedly:

‘Sudden cardiac death is a reported consequence of cocaine use. Sometimes otherwise healthy people (usually men in their 30s–40s) will literally have their heart stop when they least expect it, and just like that, it’s all over. It’s not common enough to stop everyone from using cocaine, obviously, but it happens with enough frequency that it deserves a mention’ (QN 508).

Ear, nasal and throat damage

ENT damage linked to cocaine use encompassed nasal bleeding, nasal infection and tooth decay. Nasal damage comprised septum damage mainly encountered via snorting. In some cases, users had nylon septum implants to reshape the nose. Levamisole-adulterated cocaine increased nasal bleeding and when snorted.

Cocaine-drugs interaction

When cocaine was mixed with other drugs, the effects varied depending on the drug(s) administered. The most frequent reported interaction was cocaine-levamisole interaction that often resulted in increased risk of nasal infection, immunosuppression, decreased white blood cells count, leukaemia and cardiovascular damage (unspecified). This was followed by cocaine-alcohol interaction that was associated with intense high over longer duration of action and cardiotoxicity due to formation of cocaethylene. Moreover, cocaine-alcohol interaction was linked to inhibitory effects, liver toxicity, risk of overdose and sudden death. Fatal effects and cardiovascular toxicity were also reported upon use of cocaine with opioids. More specifically, the combination of cocaine and fentanyl was reported as lethal combination. Cardiovascular toxicity was also seen upon administration of cocaine with other stimulants the resulted in increased heart rate alongside increased energy, nervousness, paranoia and rose comedown. When cut by ‘synthetic caines’, increased numbness of the nostrils was experienced. These interactions were attributed to all the ‘caines’ whether benzocaine, lidocaine or procaine.

Lethal events

Death associated with cocaine mainly followed overdose. Users reported that death could occur from cocaine irrespective of the dose, though underlying heart/lung conditions played an important role.

Social harm

Social harm reported included poor finance, homelessness, broken relationships, career problems and self-harm. Broken relationships comprised loss of contact with family and divorce. Career problems were experienced from inability to work and suffering businesses. Moreover, users lied about their addiction and health in order to escape work. Addiction to cocaine led to borrowing money, debt and homelessness. This affected psychological well-being where users attempted self-harm and exhibited scars on their body.

Discussion

This study explored e-psychonauts’ experiences associated with cocaine use from online discussion forums. Online discussion forums allowed e-psychonauts to openly discuss sensitive issues such as drug use without worrying about legal or emotional repercussions [39]. Previous studies of online discussion forums explored other drugs such as cathinones and cannabinoids [19,20,21] or solely investigated the uses of cocaine without highlighting experienced ADEs  [22].

Subsequently, the present study complemented previous studies by highlighting the users’ authentic experiences not only of desired effects but also of ADEs and reasons for using cocaine. This is crucial particularly for healthcare professionals and governmental organisations in any harm reduction approach and control of drug use. Four overarching themes were established within the study relating to cocaine characteristics and use, users’ knowledge and experience, desired effects and ADEs.

Hence in this study most users were of male sex with median age of 33-years-old. Previous literature has also found disparity between both sexes with increased usage of cocaine among males [40, 41]. Moreover, young adults have been found to use the Internet opposed to older people [42].

In relation to cocaine use, purity was found to be highest in countries of origin (Columbia, Bolivia and Peru) and decreased in distance from the source from North America to Europe as supported in previous literature [43]. Within North America, due to ports and proximity to source, Florida was found to have cocaine of highest purity [44]. The main adulterant declared was levamisole which had been found in 69% of cocaine seized by DEA [45]. Whereas in the past, the majority levamisole-adulterated cocaine had been limited to USA, Europe has been witnessing increased levamisole-adulterated cocaine over the last ten years [46, 47] and has been reported across the US and Europe [48, 49].

The main administration of cocaine was snorting which was consistent with previous research [50]. Snorting cocaine is less prone to overdose compared to IV but resulted into nasal damage that in extreme cases needed surgical intervention [51,52,53].

Users were familiar with the ADEs related to nasal and IV damage yet they preferred cocaine especially in a social context [54]. Cocaine increased confidence and sociability explaining its prevalence in social scenarios as well as drug tourism [55,56,57,58,59]. However, its use in social context did not yield only positive emotions towards the drug. Hence, sentiment analysis showed both positive and negative emotions towards cocaine. The main negative emotions were attributed to fear and annoyance and the positive emotions included interest, enjoyment and relaxation [60, 61].

The negative emotions did not stop users taking cocaine that had increased euphoric effects compared with other drugs (e.g., amfetamine) due to actions on dopaminergic and serotoninergic receptors [62, 63]. Cocaine affinity to dopamine explained the increased sexual activity associated with cocaine. Cocaine was reported as the most effective drug to increase libido and sexual performance; however, increased usage was found to deteriorate these effects [55, 64, 65].

Cocaine ADEs outweighed its desired effects as stated by e-psychonauts and were mainly attributed to nervous (NS) and CV systems. Addiction was the most prevalent nervous system ADE and was corroborated by literature exploring addiction originating from the same systems that cause euphoria [62]. Anxiety, hallucinations, paranoia and psychosis were among other NS effects resulting from cocaine use [66,67,68,69,70,71]. In addition, tachycardia and MI were the main reported CV adverse events [72,73,74,75]. Tachycardia and MI can result by two mechanisms being: (a) indirect stimulation of α-adrenergic receptors (b) prevention of re-uptake of noradrenaline and dopamine in the pre-synaptic cleft [76,77,78]. It was noteworthy to mention were not dependant on the age group, biological sex and/or acute/chronic use. The lethal effect attributed to MI was idiosyncratic where its predictability and severity were not understood [79, 80]. The effects were described idiosyncratic due to their high variability among users/abusers [80]. Hence, there were no indicators to identify people who may experience more life-threatening CV  adverse events than others upon intake of cocaine [81]. Moreover, many cocaine CV symptoms (e.g. arrhythmia) were underreported among users [80]. Sudden cardiac death was attributed to cocaine and was related to spontaneous coronary artery dissection [82].

However, NS and CV were not the only effects experienced by users where other events included nasal damage, nasal bleeding and tooth decay. Cocaine causes progressive damage to the nose leading to ischaemic necrosis of septal cartilage and septum perforation [83]. Literature has addressed the link between illicit substances such as cocaine and tooth decay and found that tooth decay was more prevalent in cocaine abuse [84].

Cocaine-drug interactions reported included mainly cocaine-alcohol and cocaine-levamisole. Cocaine-alcohol interactions were highly cardiotoxic due to production of cocaethylene and caused tachycardia and violent behaviour [85]. Cocaine-levamisole interactions caused CV toxicity, decreased white blood cells count, immunosuppression, increased risk of infection, leukaemia and neutropenia [86]. In all cases, cocaine-drug interactions were dependent on dose, route of administration and purity of the drug [87].

Not only physical ADEs were associated with cocaine, but also social harm was reported. This included self-harm, career problems and homelessness that were reported by users, and the literature has found links correlating cocaine to inward-aggression and self-harm [88, 89].

Strength and Limitations

Using discussion forums had many strengths related to data collection where it allowed in-depth understanding of cocaine use from analysis of e-psychonauts’ authentic experiences. The anonymity within the forums allowed participants to be more honest and open about their experiences without the fear of repercussions from discussing illicit drug use/abuse.

Nonetheless, many limitations were encountered in the study. The first limitation was related to the low numbers of users that reported their sociodemographic information. This is partly related to the forums being anonymous and this makes it difficult to have exact estimate of the users reporting their sociodemography, as well as the completeness and authenticity of information. Nonetheless, discussion provide a rich source of data and indepth understanding of users’ beliefs, views and experiences especially when analysed qualitatively and saturation of data is achieved. Missing information was found as a problem where data such as demography and dosage were often not reported by e-psychonauts which could have influenced results. Due to nature of the study and the anonymity within the forums it was also not possible to ask follow-up questions without breaching ethics regulations to access the missing information. There was also no method to authenticate the subjective experiences and only literature could be used opposed to biological testing (e.g., blood and hair).

Conclusion

This study found discussion forums offered a rich source of information and anonymity within the forums allowed e-psychonauts to provide honest experiences regarding cocaine use and effects. The findings of this study contributed to the scientific literature by building on present knowledge regarding cocaine purity, effects and ADEs. The most prevalent adulterants in cocaine were levamisole and procaine. Cocaine was most commonly snorted by users followed by IV administration. E-psychonauts mainly reported cocaine use in social situations due to its euphoric effects. However, cocaine was linked to many ADEs including, anxiety, paranoia, tachycardia, MI and sudden cardiac death syndrome. Moreover, it was associated with social harm that often resulted in broken relationships and homelessness.

For future research, accessing data from other social media sources (e.g., Twitter) or toxicological data can provide better understanding of cocaine on a wider platform and from different demographics. The application of machine learning algorithms will make predictions surrounding cocaine use and better understand reasons and effects associated with cocaine use. Biological testing could also be undertaken on participants to validate the subjective experiences given by e-psychonauts.

Availability of data and materials

Available upon request.

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Appendices

Appendix 1

Table 4

Table 4 ICD-11 classification for different conditions (World Health Organisation, 2019)

Appendix 2

Table 5

Table 5 SRQR checklist

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Assi, S., Keenan, A. & Al Hamid, A. Exploring e-psychonauts perspectives towards cocaine effects and toxicity. Subst Abuse Treat Prev Policy 17, 48 (2022). https://doi.org/10.1186/s13011-022-00455-5

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Keywords

  • Cocaine
  • e-psychonauts
  • Online discussion forums
  • Adverse events
  • Myocardial infarction
  • Thematic content analysis