Abstract
Introduction
The choice of a particular substance of use, like the propensity of involving in substance use, is determined by a number of factors, including the personality profiles, sociocultural milieu, availability, and accessibility of the substance, and comorbid psychopathology (1). Of these, the influence of personality traits on the choice of substance use has been studied more extensively. Externalizing characteristics such as novelty seeking and impulsivity have been found to be higher in opioid and cocaine users than alcohol users (2). Similarly, levels of constraint (negatively related to externalizing factors) have been found to be lower in opioid and cocaine users than in alcohol and marihuana users (3). However, similar personality profiles with high impulsivity and sensation seeking are seen in polysubstance users (4).
Of all the novel forms of psychoactive substance use reported, snake venom represents the potentially most lethal form. A MEDLINE and ScienceDirect review through March 2010 revealed only two reports of snake venom use for recreational purposes (5, 6). In both these reports the use of snake venom was associated with opioid use and there is evidence suggesting the use of snake venom as a substitute for morphine and in mitigating opioid withdrawal (7). These findings make the study of snake venom use as a psychoactive substance interesting from a clinical as well a neurobiological perspective. Keeping this in view, we report a series of two patients with multiple substance use disorders who resorted to occasional snake bites for recreational purposes to discuss the possible mechanisms for the psychoactive properties of the snake venom, the predisposing factors for such novel and dangerous recreations, and the clinical and research implications of this intriguing phenomenon.
Methods
A case series of two patients who presented to the outpatient facility of the Centre for Addiction Psychiatry, Central Institute of Psychiatry, Ranchi, India (a tertiary referral treatment center).
Case Reports
Case 1
Mr. PKD, a 52-year-old married male with a history of substance use for past 34 years started taking alcohol at the age of 18 and over the years he added cannabis, benzodiazepines, and opioids over different periods of time and in varying combinations to produce the desired effects. History revealed a concurrent as well as simultaneous dependence pattern of substance use on all the aforementioned substances for varying durations over the past 34 years. The patient's first contact with the de-addiction services was only 4 years back and since then he had been detoxified four times in an inpatient facility and put on a maintenance treatment of naltrexone 50 mg/day. Two months before contacting our center, the patient learned of the intoxicating effects of snake venom through some of his friends and, as reasoned by the patient, he decided to try it in order “to experience the kick the other substances now lacked.” With the help of the nomadic snake charmers common in India, the patient subjected himself twice to the snake bite over his left forearm over a period of 15 days. There was no local tissue injury at the site of the bite apart from the bite marks. The patient described a feeling of dizziness and blurred vision followed by a heightened arousal and sense of well-being lasting a few hours; a more intense state of arousal than he would experience with pentazocine injections. The patient was not able to identify the snakes used but was apprehensive about the risks involved in the process. A multidimensional assessment of personality done using Revised NEO Personality Inventory (NEO-PI-R) revealed elevated scores on the dimensions of Neuroticism (54), Extraversion (59) and Openness (56), Agreeableness (49), and Conscientiousness (59) (8).
Case 2
Mr. SKG, a 44-year-old married male with a history of substance use for the past 29 years started taking nicotine at the age of 15 years, followed by cannabis at around 17 years and alcohol, benzodiazepines, and opioids in the years following. Intake history revealed a concurrent dependence on all aforementioned substances for varying durations over the past 29 years, with opioid as the predominant substance of choice. During the interview it was revealed that the patient would engage in socially disapproved activities like harassing his relatives and neighbors, and robbery along with his fellows and was undergoing trial for an alleged robbery. The patient's drug-abuse and antisocial behaviors strained his relationship with his parents and, later, with his wife as well. These behaviors would persist apart from his substance taking behavior. The patient's first contact with the de-addiction services was 10 years back. During that time, he had been detoxified six times in an inpatient facility and been treated with naltrexone 50 mg/day and buprenorphine 4 mg/day at different times. A month prior to contacting our center, the patient learned of the use of snake bite as a means of getting high. Presenting to a location in an urban slum where this service was readily available, he subjected himself to being bitten once on his left foot by a small Indian cobra (Naja naja). The patient described the experience as a blackout associated with a sense of well-being, lethargy, and sleepiness. He slept overnight at the same place and awoke the next morning without any residual effect. There was no local tissue injury at the site of the bite apart from the bite marks. A multidimensional personality assessment done using NEO-PI-R revealed high scores on the dimensions of Neuroticism (68), Extraversion (62) and Openness (63), and low scores on Agreeableness (33), and Conscientiousness (38).
Discussion
Generally, envenoming bites by elapids and hydrophiids produce neurotoxicity with little or no local tissue injury. Bites by viperids and crotalids, however, lead to vasculotoxicity, producing severe local tissue injury. There is evidence that some crotalids and elapids can produce a combination of both aforementioned effects (9). The absence of any local tissue injury apart from the bite marks, the identification of the snake as cobra by one of our patients, and the wide distribution and easy availability of the elapids (cobras and kraits, especially with the snake charmers) in India and the symptoms (dizziness, blurred vision, lethargy) experienced by our patients all point to a neurotoxic nature of envenomation in our patients (9). The neurotoxic effects of the elapid envenomation result mainly from 2 types of toxins—neurotoxins and dendrotoxins. Of the neurotoxins, the α-neurotoxins competitively bind to the postsynaptic neuronal and skeletal muscular nicotinic cholinergic receptors (nAChRs), leading to muscular paralysis (10). There is also evidence to show that some of the α-neurotoxins result in a centrally mediated opiate-independent analgesia through the nAChRs and can substitute morphine and mitigate opioid withdrawal (7, 11). Given the role of nAChRs in rewarding or euphoric experiences associated with substance use mediated through the mesolimbic dopaminergic system, it seems plausible to assume that the pleasurable experiences described by our patients may be mediated by the same pathway (12). However, such conclusions can only be hypothesized and require further research.
Exploring the rationale employed in willfully and willingly subjecting oneself to potentially lethal snake bites as a source of recreation is an interesting process. High levels of sensation seeking and impulsivity in multiple substance users have been related to the use and experimentation of a wide range of substances, including the more deviant ones (4). The multiple substance use in our patients and the involvement of one of our patients in dissocial behaviors, indicating high sensation seeking, seems to have contributed to their vulnerability to resort to a novel substance use in the form of snake bite. The NEO-PI-R profiles of our patients indicating high levels of extraversion (representing high energy and preference for excitement and stimulation), openness (representing openness toward different experiences), and neuroticism (especially high scores on impulsiveness) seem to be consistent with their substance intake patterns (4, 13). However, the association of similar personality profiles with polysubstance use irrespective of the choice of the substance and the absence of any studies on the personality dimensions of this type of potentially lethal substance use behavior precludes us from drawing any definitive conclusions.
As mentioned earlier the choice of a particular substance of use results from an interplay of multiple factors—cultural milieu being one of these. The facts that snakes share a reverential place in Hindu mythology, are worshipped in the Indian culture, and are easily available seem to have contributed to the choice of using this potentially lethal form of substance use (14).