Lymphatic filariasis is the most widespread of human filarial infections, a group of vector-borne infestations. After the discovery of diethylcarbamazine (DEC), little advance was made in the development of new chemotherapeutic agents for the treatment of lymphatic filariasis until 1985. Since then, several new initiatives have occurred as the result of a global effort by the World Bank/UNDP/WHO Special Programme on Tropical Diseases and the Onchocerciasis Control Programme. Some of these global research initiatives are reviewed in this paper. Recent observations throw a new light on the rational use of DEC including its deployment as a medicated salt. Ivermectin, an established drug for the treatment of river-blindness is examined for its potential use in the treatment of lymphatic filariasis. Experimental results from two novel compounds out of several being developed by the WHO/OCP Macrofil project are considered in respect to their potential macrofilaricidal activity, particularly in relation to lymphatic filarial infections.
Epidemiological studies are carried out by the National Drug Research Centre, Malaysia on various aspects of drug use and abuse. One of the groups of substances studied are the opioid agonist-antagonists. The study utilised information submitted to international agencies and obtained through a questionnaire survey. The results showed that out of 28 countries studied, 18 reported existence of illicit traffic in these substances and of this, 17 indicated seizures. A majority of countries were unable to give consumption data and the limited information available did not allow any significant conclusions. The study did not demonstrate a significant problem of abuse globally.
Although those Malaysian secondary schoolchildren who have never used drugs are consistent in their support for legal and social sanctions against drug use, it is argued that such sanctions are a relatively unimportant factor in the decision whether or not to use drugs. Non-drug users inhabit a social world separated from their drug-using contemporaries; they rely on information from public rather than direct social sources, and claim to have been little interested in information received. However, there is evidence that, for a minority of the drug-using sub-sample, public information campaigns have made them more rather than less interested in experimenting with drug substances.
Information from the national drug abuse monitoring system was analysed to determine the trends in extent and pattern of drug dependence in Malaysia over the period 1970 to 1986. The annual incidence and prevalence rates of reported drug dependents increased by many folds when compared to the early seventies. Generally, the profile of drug dependents identified has remained relatively stable throughout the years. A stable pattern of drug abuse was also noted over this period. Factors influencing the trend patterns are discussed, as well as the implications of these findings for policy purposes.
The temporal sequence of drug use should reveal which drugs are precursors to heroin and which drugs are used subsequent to the establishment of heroin addiction as adjunctive drugs. This temporal sequence was examined in an epidemiological study. Out of 249 opiate addicts interviewed in the area of Penang, Malaysia, this sequence of drugs could be obtained in 248 cases. The mean (median) age for first use of nicotine is 15.5 (15) years, alcohol 18.4 (18) years, cannabis 17.8 (17) years, heroin 21.8 (21) years, opium 22.8 (22) years, and benzodiazepines 25.8 (25) years. The age of first use of different drug types is presented in some detail. The patterns of sequence of drug use was analyzed for the five major and most frequently reported drugs, i.e. alcohol, cannabis, heroin, opium and benzodiazepines. Nicotine, used as first drug in almost all cases, was omitted in this analysis. A clear trend to multiple drug abuse emerges from this analysis; the biggest number of cases were users of 4 drugs (81 cases), followed by 3 drugs (59 cases) and 5 drugs (58 cases). Thus, nicotine, alcohol and cannabis are precursors of heroin addiction. Other adjunctive drugs become important only after heroin addiction. Among these substances, opium and benzodiazepines are numerically preponderant.
A representative sampling of the secondary school population of two states of Malaysia (sample size 16166) indicated that 11% of students had had experience of drug use. Use of a single drug was the common pattern, with cannabis reported most often by older students, and sedatives most often by younger students. A quarter of those who had used drugs reported experience with four or more substances and were likely to have progressed rapidly to heroin. This progression may be facilitated by the ready availability of heroin and the local tradition of smoking or inhaling rather than injecting opiates. Descriptions of drug migration patterns based on Western samples are not fully appropriate worldwide, because the youthful abuser is much influenced both by local market forces and by cultural traditions, even though the epidemic of youthful drug abuse is itself worldwide.
Monitoring systems are useful epidemiological instruments for assessing the problem of drug abuse. The rapid growth of the drug dependence problem in Malaysia led to increased awareness of the need for a system for continuous monitoring of the situation. Preliminary work on the design of an appropriate monitoring system was initiated in 1976. A fully integrated national reporting system was established in 1978, linking all public services and agencies coming into contact with drug-dependent persons, including law enforcement agencies, drug abuse treatment and rehabilitation centres, and social and welfare institutions. The information system included a mechanism for systematic gathering, processing, analysing and presenting essential data on the prevention, control and management of drug abuse problems. It also included reporting on drug-related events, such as hospitalizations and arrests, as well as data on known drug-dependent persons and new cases of dependence. The system has been used for routine monitoring of the extent, trends, patterns and other characteristics of drug abuse problems in Malaysia, providing basic information for policy-making and programme planning. On the basis of data generated by the system, it was estimated that the prevalence rate of drug-dependent persons per 100,000 population increased from 84.3 in 1976 to 754.6 in 1986. It was estimated that there were 119,001 drug-dependent persons in Malaysia in 1986.
In a recent epidemiological study of 249 opiate addicts in the State of Penang, Malaysia, the use of benzodiazepines, its temporal relationship to opiate addiction and the reasons for use of benzodiazepines were examined. Just over a half of the opiate addicts indicated use of benzodiazepines in their lifetime. Use of 7 different benzodiazepines was reported, among them flunitrazepam most frequently. A substantial proportion had discontinued the use of benzodiazepines after initial experimentation. Just over a quarter had used them in the last 24 hours. Benzodiazepine use starts on average 3 to 6 years later than heroin use. The most common reason cited for benzodiazepine use was to enhance the feeling of 'high' from the opiates. These findings can be explained, at least partly, by economic factors. Reasons that could be qualified as attempts to autotherapy did not exceed 20%. None of the opiate addicts had reported isolated benzodiazepine use for fun and pleasure. From the time course of use as well as from the reasons given by the addicts, it is evident that benzodiazepines are not primary drugs of abuse. Comparing their figures from Malaysia with figures from Germany and England the authors cannot explain the preferred use of flunitrazepam by Malaysian addicts by the existence of special properties of this substance.
The present paper is the third and concluding part of a study of the secondary school population of two of Malaysia's thirteen states, Penang and Selangor. Since completion of the two earlier papers, the research team has investigated the pattern and nature of drug use among the equivalent population in a third state, Kelantan, and has again found essentially the same pattern of results: youthful drug use is most clearly related to precocious self-assertion, and a set of beliefs and attitudes about drugs and drug taking, and is largely unrelated to indicators of social deprivation or personal problems. The significance of this repeated finding in Kelantan is that, in this much more rural and traditional state, adult and established patterns of drug use had historically differed considerably from those found in the two more urban and cosmopolitan states of Penang and Selangor. Our findings indicate that the new pattern of drug use by youth has transcended the older cultural differences between the states, and is in turn explained by a more universally familiar set of characteristics in adolescent development.
Those Malaysian secondary schoolchildren who have ever used an illicit drug do not differ significantly in terms of social class background, ethnicity or rural/urban location, from the majority of their contemporaries who have not used drugs. The cross-sectional data show a rapid secular trend towards the sexes being equally involved in drug use. Significant differences between ever and never users are, however, found in their attitudes towards drug taking and their beliefs about the properties of drugs, although both groups share the same rather negative image of the typical drug user. Thus, drug users have accepted some of the attitudes towards drug issues which are normative in the non-user group, whilst developing other attitudes which are consistent with their continuing use. It is argued that adolescent drug abuse in Malaysia is not to be linked specifically with social deprivation, but should be seen as being part of the life style of particular groups in all strata of society.
In a study of 249 opiate (mainly heroin) addicts special attention was paid to adjunctive drug use. Generally, nicotine (cigarette smoking), alcohol and cannabis preceded the use of heroin, and continued to be used as adjunctive drugs after the establishment of heroin addiction. Nicotine was the most common substance used together with opiates. Alcohol and cannabis were used as adjunctive drugs in about two-thirds of the cases. In the late stages of heroin addiction, benzodiazepines were also used concomitantly with opiates. The most frequently reported reason for the use of adjunctive drugs was to intensify the effect of the opiate. Three-quarters or more of the addicts had used different adjunctive drugs to boost the euphoric feeling derived from the primary drug, i.e. heroin. Attempt at self-treatment of withdrawal symptoms was a less frequently reported reason for adjunctive drug use. The findings show that heroin addiction is the major problem. The use of adjunctive drugs, especially benzodiazepines, can be partly explained on economic grounds. They must be clearly distinguished from the primary drug of abuse, heroin. For policy-making decisions, it is important that the elimination of heroin abuse through effective prevention measures would ultimately wipe out the problem of adjunctive drug use, while reduction of the overall supply of heroin without reduction in actual demand might result in an increasing trend to adjunctive drug use.
The study explores how data collated from rapid assessment can enhance those produced by national level surveillance systems, in this case the national drug information (NADI) system in Malaysia. Qualitative data were collected in keeping with internationally accepted guidance on rapid assessment methods in the field of substance use. An inductive research strategy was employed. The rapid assessment produced multiple data on local drug use practices and how these were influenced by the contexts of use. The assessment points to the importance of collecting data not only on patterns of drug use but also on the health and social consequences of drug use. We suggest that the current national drug information system places greater emphasis on behavioural and health-related variables in order to better understand the potential relationships between drug use and health-related risk, including HIV/AIDS.
The divine tree neem (Azadirachta indica) is mainly cultivated in the Indian subcontinent. Neem has been used extensively by humankind to treat various ailments before the availability of written records which recorded the beginning of history. The world health organization estimates that 80% of the population living in the developing countries relies exclusively on traditional medicine for their primary health care. More than half of the world's population still relies entirely on plants for medicines, and plants supply the active ingredients of most traditional medical products. The review shows the neem has been used by humankind to treat various ailments from prehistory to contemporary.
The authors selected 38 thin-layer-chromatography (TLC) systems described in the available literature published over the last 10 years and evaluated those systems with respect to their suitability for detection and identification of opiates in urine, opium and heroin, as well as adulterants in heroin. A total of 14 substances: 8 opiates (morphine, 6-monoacetylmorphine, diacetylmorphine, codeine, acetylcodeine, noscapine, papaverine and thebaine) and 6 adulterants (ephedrine, quinine, methadone, caffeine, cocaine and strychnine) were used as test samples for this research. Using laboratory-coated plates and pre-coated plates, 15 and 13 TLC systems, respectively, were found to be able to detect and identify morphine and codeine in urine without interference from the remaining 12 substances. For the detection of opiates in opium samples as well as opiates and adulterants in illicit heroin samples the TLC system: chloroform-n-hexane-triethylamine (9:9:4) which was developed by the National Drug Research Centre, Penang, Malaysia, was found to be most suitable on both laboratory-coated and pre-coated plates. In addition, the following two systems, one on laboratory-coated plates--hexane-chloroform-diethylamine (50:30:7)--and the other on pre-coated plates--benzene-dioxane-ethanol-ammonia (50:40:5:5; T-7)--were also found to be among most suitable TLC systems for the analysis of opiates in opium samples. The article also presents the relative cost of each of the 38 evaluated TLC systems.
There has been a rapid increase in the past five years in the numbers of hospitalized drug dependents. While the studied population was clearly unrepresentative of the country-wide drug using population, it illustrates how the problem is neither limited to one particular stratum of society, nor to the few "traditional" drugs. Indeed, an increasingly youthful group of individuals drawn from all backgrounds is not only becoming dependent upon opiates, but is also using a range of other drugs, all of which are available on the market at relatively low cost. The market prices of drugs have an effect on the pattern of drug use; and many individuals move directly from tobacco to heroin smoking. Drug abuse continues to be a considerable public and governmental concern, and enforcement and treatment programmes are rapidly expanding in attempts to resolve this problem.
Drug addiction is an important social problem in many countries. Genetic and environmental factors contribute to the predisposition of drug addiction. Genetic variations at the μ opioid receptor (OPRM1) gene locus have been associated with opiate addiction. The present study aims to delineate the frequency of A118G allele of OPRM1 among Malaysian subjects. The frequency of A allele and G allele were 51% and 49%, respectively for addicts and about 73% and 27% respectively for healthy volunteers. The frequency of G allele was 1.77-fold higher in addicts by odds ratio calculation at 95% Cl, which indicate the G allele to be strongly associated with addiction X(2) = 15.31,P < 0.0001; odds ratio 2.51; 95% Cl (1.575-3.994), compared to healthy volunteers. A significant association was observed between A118G polymorphism in μ opioid receptor gene and drug addiction.
Despite the growing HIV threat among injecting drug users (IDUs) in Malaysia, there is a dearth of information on their HIV risk behaviour. This study focused on identifying specific risk behaviours that distinguished HIV positive IDUs from those who were not. For the first time, data on IDUs not in treatment were obtained through a cross-sectional survey of 526 subjects recruited from five selected cities across peninsular Malaysia. A structured questionnaire and face-to-face interviews were utilised to collect detailed information on their drug use practices and sexual behaviours. On-site serological testing determined their HIV and hepatitis C status. The findings indicated that ethnic Malays, who are also Muslims, form the majority of IDUs not in treatment. Bivariate analysis identified six risk factors associated with HIV seropositivity: being 44 years or younger; not holding a regular job; initiating drug use at age 23 or younger; being a morphine user; sharing injecting equipment and having multiple-sex partners. However, only the last two remained significant in multivariate analysis. That sharing contaminated injecting equipment is a significant risk factor strongly justifies the widening of the pilot needle and syringe exchange programme initiated hesitantly in late 2005 as a reaction to the worsening HIV/AIDS situation. Condom use, though not independently significant, remains important because consistent and wider use could neutralise the second risk factor--having multiple-sex partners. The finding that injecting drug use is increasingly occurring in groups underscores the need for outreach programmes that emphasise safe injecting practices in group settings. In addition, counsellors should endeavour to convince drug users to enter treatment since being in treatment appears to reduce risk behaviours. Finally, conservative Muslim unease about harm reduction must be assuaged quickly since Malay Muslims form the majority of IDUs not in treatment.
The prevalence of hepatitis C virus (HCV) among heroin dependants in treatment was estimated at 89.9%; however, virtually no information exists on the prevalence or risk behaviour among the larger population of drug users not in treatment. This study assessed the prevalence of HCV and associated risk factors among this group with a view to designing more effective intervention programs.
CGI 18041, an adduct of benzothiazol isothiocyanate N-methyl piperazine, was evaluated for its antifilarial properties in subperiodic Brugia malayi infected Presbytis cristata. Animals experimentally infected with 200-400 subperiodic Brugia malayi infective larvae, were matched according to microfilaria density, infective dose, and duration of infection. They were then randomly assigned to various treatment and control groups. The compound was suspended in 1% Tween 20 in distilled water, sonicated, and then fed to monkeys using a stomach tube. Control animals received an equivalent volume of drug diluent. CGI 18041 at a single oral dose of 50 mg/kg had complete adulticidal and microfilaricidal activities against subperiodic B. malayi in P. cristata. It was also extremely effective at a single dose of 25 mg/kg, the final geometric mean microfilaria count being 1.6% of initial level, and only 1.0% of the infective dose was recovered as live adult worms at autopsy 6 weeks post-treatment. In control animals, these were 226.9% and 5.56% respectively.