Evidence For Self-medication Research Articles

Evidence of Self-Medication with Chloroquine before Consultation for Malaria in the Southern Pacific Coast Region of Colombia.

Self-medication with antimalarial drugs is a major factor in the development of drug resistance, exerting subtherapeutic drug pressure on circulating parasite populations. Data on self-medication with antimalarials from the Southern Pacific coast region of Colombia, where 4-aminoquinolines resistance and political instability prevail, are vital to elimination strategies. We present results of an exploratory study of 254 individuals having malaria symptoms who sought malaria diagnosis in two hospitals in Tumaco, Department of Nariño, Colombia. Thirty-two percent (82/254) of participants had positive Saker-Solomons urine tests, indicating self-medication with chloroquine (CQ) before consultation for diagnosis. Notably, among 30 pregnant women participating in the study, 43% were Saker--Solomons positive. Molecular analysis of the K76T position encoded by the pfcrt gene revealed the mutant allele in all four samples that were both positive for Plasmodium falciparum and positive for the Saker-Solomons test, suggesting persistent CQ pressure. The high frequency of self-medication, particularly among pregnant women merits attention by public health authorities and comprehensive investigation.

Neanderthal behaviour, diet, and disease inferred from ancient DNA in dental calculus.

Recent genomic data have revealed multiple interactions between Neanderthals and modern humans, but there is currently little genetic evidence regarding Neanderthal behaviour, diet, or disease. Here we describe the shotgun-sequencing of ancient DNA from five specimens of Neanderthal calcified dental plaque (calculus) and the characterization of regional differences in Neanderthal ecology. At Spy cave, Belgium, Neanderthal diet was heavily meat based and included woolly rhinoceros and wild sheep (mouflon), characteristic of a steppe environment. In contrast, no meat was detected in the diet of Neanderthals from El Sidrón cave, Spain, and dietary components of mushrooms, pine nuts, and moss reflected forest gathering. Differences in diet were also linked to an overall shift in the oral bacterial community (microbiota) and suggested that meat consumption contributed to substantial variation within Neanderthal microbiota. Evidence for self-medication was detected in an El Sidrón Neanderthal with a dental abscess and a chronic gastrointestinal pathogen (Enterocytozoon bieneusi). Metagenomic data from this individual also contained a nearly complete genome of the archaeal commensal Methanobrevibacter oralis (10.2× depth of coverage)-the oldest draft microbial genome generated to date, at around 48,000 years old. DNA preserved within dental calculus represents a notable source of information about the behaviour and health of ancient hominin specimens, as well as a unique system that is useful for the study of long-term microbial evolution.

Primate Self-Medication, Passive Prevention and Active Treatment - A Brief Review

Parasites and pathogens are a source of diseases that can affect the health, behavior and reproductive fitness of an individual. The study of animal self-medication as a science is relatively new, but traditional societies have long looked to animals for clues to nature’s medicine cabinet. Evidence of self-medication is widespread throughout the animal kingdom. To date, research has classified health maintenance and self-medicative behaviors into five levels: 1) ‘sick behaviors’; 2) behavioral avoidance or reduction of the possibility for disease transmission; 3) dietary selection of items with a preventative or health maintenance effect; 4) ingestion of a substance for the curative treatment of a disease or the symptoms thereof, and; 5) application of a substance to the body or a living space for the treatment or control of vectors or external health condition. Among the groups of animals studied to date, primates have provided the most details for level 3 and 4 behaviors, exemplified by such diverse dietary selection and behaviors as bitter pith chewing and whole leaf swallowing behaviors, used directly in response to increased levels of parasite infection. KEYWORDS: Animal self-medication, primates, medicinal plants, disease control, homeostasis

Further evidence of self-medication: personality factors influencing drug choice in substance use disorders.

According to Khantzian's (2003) self-medication hypothesis (SMH), substance dependence is a compensatory means to modulate affects and self-soothe in response to distressing psychological states. Khantzian asserts: (1) Drugs become addicting because they have the power to alleviate, remove, or change human psychological suffering, and (2) There is a considerable degree of specificity in a person's choice of drugs because of unique psychological and physiological effects. The SMH has received criticism for its variable empirical support, particularly in terms of the drug-specificity aspect of Khantzian's hypothesis. We posit that previous empirical examinations of the SMH have been compromised by methodological limitations. Also, more recent findings supporting the SMH have yet to be replicated. Addressing previous limitations to the research, this project tested this theory in a treatment sample of treatment-seeking individuals with substance dependence (N = 304), using more heterogeneous, personality-driven measures that are theory-congruent. Using an algorithm based on medical records, individuals were reliably classified as being addicted to a depressant, stimulant, or opiate by two independent raters. Theory-based a priori predictions were that the three groups would exhibit differences in personality characteristics and emotional-regulation strategies. Specifically, our hypotheses entailed that when compared against each other: (1) Individuals with a central nervous system (CNS) depressant as drug of choice (DOC) will exhibit defenses of repression, over-controlling anger, and emotional inhibition to avoid acknowledging their depression; (2) Individuals with an opiate as DOC will exhibit higher levels of aggression, hostility, depression, and trauma, greater deficits in ego functioning, and externalizing/antisocial behavior connected to their use; and (3) Individuals with a stimulant as DOC will experience anhedonia, paranoia, have a propensity to mania, and display lower levels of emotional inhibition. MANOVAs were used to test three hypotheses regarding drug group differences on the personality variables that were in keeping with the SMH. The MANOVAs for Hypothesis I (Depressant group) and Hypothesis II (Opiate group) were statistically significant. Findings partially support the SMH, particularly in its characterization of personality functioning in those addicted to depressants and opiates.

Self-medication with tannin-rich browse in goats infected with gastro-intestinal nematodes

Primates self-medicate to alleviate symptoms caused by gastro-intestinal nematodes (GIN) by consuming plants that contain secondary compounds. Would goats display the same dietary acumen? Circumstantial evidence suggests they could: goats in Mediterranean rangelands containing a shrub – Pistacia lentiscus – with known anthelmintic properties consume significant amounts of the shrub, particularly in the fall when the probability of being infected with GIN is greatest, even though its tannins impair protein metabolism and deter herbivory. In order to test rigorously the self-medication hypothesis in goats, we conducted a controlled study using 21 GIN-infected and 23 non-infected goats exposed to browse foliage from P. lentiscus, another browse species – Phillyrea latifolia, or hay during the build-up of infection. GIN-infected goats showed clear symptoms of infection, which was alleviated by P. lentiscus foliage but ingesting P. lentiscus had a detrimental effect on protein metabolism in the absence of disease. When given a choice between P. lentiscus and hay, infected goats of the Mamber breed showed higher preference for P. lentiscus than non-infected counterparts, in particular if they had been exposed to Phillyrea latifolia before. This was not found in Damascus goats. Damascus goats, which exhibit higher propensity to consume P. lentiscus may use it as a drug prophylactically, whereas Mamber goats, which are more reluctant to ingest it, select P. lentiscus foliage therapeutically. These results hint at subtle trade-offs between the roles of P. lentiscus as a food, a toxin and a medicine. This is the first evidence of self-medication in goats under controlled conditions. Endorsing the concept of self-medication could greatly modify the current paradigm of veterinary parasitology whereby man decides when and how to treat GIN-infected animals, and result in transferring this decision to the animals themselves.

Commentary on Sartor et al. (2013): Trauma and drug use—more evidence for self‐medication?

Commentary on Sartor <i>et al</i>. (2013): Trauma and drug use—more evidence for self‐medication?

Interactive effects between diet and genotypes of host and pathogen define the severity of infection

Host resistance and parasite virulence are influenced by multiple interacting factors in complex natural communities. Yet, these interactive effects are seldom studied concurrently, resulting in poor understanding of host-pathogen-environment dynamics. Here, we investigated how the level of opportunist pathogen virulence, strength of host immunity and the host condition manipulated via diet affect the survival of wood tiger moth Parasemia plantaginis (Arctidae). Larvae from “low cuticular melanin” and “high cuticular melanin” (considered as low and high pathogen resistance, respectively) selection lines were infected with moderately and highly virulent bacteria strains of Serratia marcescens, while simultaneously manipulating host diet (with or without antibacterial compounds). We measured host survival and food preference before and after infection to test whether the larvae “self-medicate” by choosing an anti-infection diet (Plantago major, i.e., plantain leaf) over lettuce (Lactuca sativa). “High melanin” larvae were more resistant than “low melanin” larvae to the less virulent strain that had slower growth and colonization rate compared with the more virulent strain. Cuticular melanin did not enhance survival when the larvae were infected with the highly virulent strain. Anti-infection diet enhanced survival of the “high melanin” but not the “low melanin” hosts. Survival was dependent on family origin even within the melanin selection lines. Despite the intrinsic preference for lettuce, no evidence of self-medication was found. These results demonstrate that the relative benefit of host cuticular melanin depends on both diet and pathogen virulence: plantain diet only boosted the immunity of already resistant “high melanin” hosts, and cuticular melanin increased host survival only when infected with moderately virulent pathogen. Moreover, there was considerable variation in host survival between families within both melanin lines suggesting genetic basis for resistance. These results indicate that although melanin is an important predictor of insect immunity, its effect on disease outcomes greatly depends on other interacting factors.

Dazed and Confused by Self-Medication

To the Editor: Dual diagnosis may be the most pervasive and challenging problem we face in psychiatry that receives the least sufficient or coherent attention. In their article published in the January 2010 issue of the Journal, Denise A. Hien, Ph.D., et al. (1) examined how improvement in posttraumatic stress disorder (PTSD) symptoms as a result of treatment affects substance use outcomes, exemplifying the sort of longitudinal, diagnostically inclusive experimental designs we need. However, I am left dazed and confused by the selfmedication framework the article, and much of the best dualdiagnosis research, so dogmatically espouses. The article begins with defining the importance of this research: “The co-occurrence of (PTSD) and substance use disorders is a major public health concern…because of negative physical and mental health consequences and poor treatment outcomes” (1, p. 95). Yet, the main conclusion of the study was that PTSD patients use substances to self-medicate symptoms. Initial PTSD symptom reduction often precedes substance use disorder reduction, while early substance use disorder improvement does not as robustly lead to PTSD symptom improvement. This is interpreted exclusively as evidence for self-medication. However, these data could reflect a change in a neurobiological state that drives both PTSD symptom severity and compulsive drug-taking that has nothing to do with whether substance use impacts PTSD symptoms in the same manner that treatment with medication affects these symptoms. Exclusive support for self-medication would require not a relative lack of PTSD symptom reduction after substance use disorder improvement (as shown in the article) but an increase in symptoms after substance use reduction (which was not shown). Following the self-medication framework, it was never mentioned that the results also showed that if substance use disorders initially decline either alone or along with declining PTSD symptoms, patients are less likely to relapse to a total (both PTSD and substance use disorder symptoms) nonresponse condition relative to what initial PTSD symptom-alone improvement predicts. In the comparative treatments, trauma-focused/seeking safety versus health education, the former achieved superior efficacy for severe dual diagnosis. The authors explained that trauma-focused/seeking safety “is an integrated cognitive behavior approach that actively links PTSD symptoms with ‘unsafe’ substance use behavior” (1, p. 97). This implies, as shown in bipolar patients (2), that when cognitive-behavioral therapy (CBT) acts to dispel the notion that the link between psychiatric symptoms and substance use is somehow positive (e.g., that it represents self-medicating) and replaces it with a concept that it is detrimental (e.g., that it is a disorder), you actually get superior efficacy. At baseline, more severe PTSD was associated with more severe substance abuse, a finding replicated often in the dual-diagnosis literature but once again interpreted only as evidence of self-medication. However, if we think about drugs proven to help psychiatric symptoms (i.e., psychiatric medications), we find that medication compliance (i.e., self-medication) is often actually worse with greater illness severity. Moreover, for these medications with which patients clearly use to self-medicate, it would be illogical to conclude that since the individuals taking the medications are sicker than the individuals who are not, the medications are actually being used to medicate the illness.

Sheep self-medicate when challenged with illness-inducing foods

People learn to take aspirin for headaches, antacids for stomach aches and ibuprofen to relieve pain, and often obtain prescriptions from doctors for medications. Is it also possible that herbivores write their own prescriptions? From prehistoric times, people have looked to the presumed self-medicative behaviour of animals for remedies of ailments but it is still not clear whether animals seek medicinal compounds to recuperate from illness. Evidence of self-medication is based almost exclusively on observations rather than experimental analyses. We examined whether lambs select specific protective chemicals to recuperate from ingesting malaise-inducing foods. In pen studies, lambs in a treatment group were conditioned to consume foods and toxins (grain, tannins, oxalic acid) that led to negative internal states and then allowed to eat a substance known to attenuate each state (sodium bentonite, polyethylene glycol and dicalcium phosphate, respectively). Control lambs ate the same foods and medicines, but disassociated temporally, so they did not recuperate from illness. After conditioning, lambs ingested grain or food with tannins or oxalates and then received a choice of the three medicines. Only the treatment animals preferred to eat the specific compound known to rectify the state of malaise induced by the food previously ingested. Control animals never changed their pattern of use of the medicines, regardless of the food consumed before the choice. This first demonstration of multiple malaise–medicine associations supports suppositions in zoopharmacognosy and current hypotheses of homeostatic endeavour, and has implications for the well-being of wild and domestic animals.