Medicine potential toxic

Hazardous Substances Data Bank (HSDB) on compact disc from the Canadian Center for Occupational Health and Safety (can buy at CCOHS web site). "The HSDB(R) (Hazardous Substances Data Bank(R)) database contains data profiles on 4,500 potentially toxic chemical substances. It is created and updated by specialists at the U.S. National Library of Medicine. Compiled from an extensive range of authoritative sources, HSDB is widely recognized as a reliable and practical source of health and safety information. Much of the data is peer reviewed. 

In many developing countries of the world, there is still a major reliance on crude drug preparation of plants used in traditional medicines for their primary health care. Pharmacognosists employed in the different institutions are aware of the changing trends of herbal medications and a number of useful texts on the analysis, uses, and potential toxicities of herbal remedies have appeared recently, which serves as useful guides in pharmacy practice. The history of medicine includes many ludicrous therapies. Nevertheless, ancient wisdom has been the basis of modem medicine and will remain as one important source of future medicine and therapeutics. The future of natural products drug discovery will be more holistic, personahzed and involve the wise use of ancient and modem therapeutic skills in a complementary manner so that maximum benefits can be accmed to the patients and the community. 

We are exposed to plant products (many of the earlier drugs and most of the herbal pharmacopoeia in use today are crude plant extracts), some of which are potentially toxic, as, less commonly, are foods of animal origin. Medicinal drugs are just one of a set of chemicals which are exposed to the range of defence mechanisms put up by the body to protect it from the onslaught of foreign chemicals. 

During the first half of the century, there was virtually an exclusive reliance on animal testing as the primary model for drug discovery and development. New chemical entities were administered to rodents in the primary screen assay, and the appropriate responses were monitored for indications of therapeutic potential. Compounds meeting the appropriate potency and efficacy criteria were promoted to more diverse and sophisticated animal models to characterize their pharmacological profile. The responses that were monitored included blood pressure (hypotensives), latency to respond to painful stimuli (analgesics), attenuation of seizure propensity (antiepileptics) and other responses that were intuitively and pharmacologically valid indicators of medicinal potential or toxicity. Some of these methods were semiautomated and quite sophisticated for their time, particularly for cardiovascular indications [1]. 

Much emphasis has been given in the past two years to the possible toxicity of nanoparticles, by both media and scientific journals, with a general fear that they might turn up in an occupational and environmental disaster, as with asbestos, or become a serious and debated issue, like OGM. Because of their peculiar physical and chemical features, the study of nanoparticles as potential toxic agents requires a multidisciplinary approach involving disciplines from physics chemistry to biology and medicine. 

The introduction of antibiotics into clinical medicine has brought about a whole range of unforeseen problems. Apart from potential toxicity and, with some antibiotics, such as penicillins, of hypersensitivity reactions, several micro-organisms (especially many types of bacteria) show high levels of resistance. Furthermore, transferability of resistance from resistant to sensitive cells of the same or different species or genus is a well-known phenomenon with potentially serious clinical consequences [6-8],... 

Despite the potential toxicity that could be associated with many medicinal plants, the local people have for centuries been using them as recipes for traditional medicines. They have in many cases been able to effectively control possibilities of toxicity through knowledge handed down from forefathers. One way of eliminating potential toxicity of extracts by the herbal practitioners is by burning their herbal preparations before dispensing. This was evident in the present study where many of the herbal preparations used for skin infections would be burnt into powder first before application. 

The amount of scientific information contained in a licensing application may be vast (often exceeding 1000 pages). The pharmaceutical company presents evidence to show that every aspect of production of the medicinal product has been controlled and validated and is of an acceptable quality. The application starts with a description of the discovery chemistry for the new drug. This may be a chemical synthesis or an extraction of an active natural product from a plant or microorganism. Spectroscopic (e.g. NMR, MS, IR) and chromatographic (e.g. HPLC, GC) data are presented to show that the correct compound has been synthesised, and that by-products are identified and their levels controlled. The new chemical entity is then subjected to stability testing under accelerated conditions of heat, humidity, etc. to calculate shelf-life and rates of decomposition. Each decomposition product is identified and any potential toxicity is controlled. 

Fumigation against pests is a conrmon practice in traditiorral medicine shops. However, shop owners do not appear to be concerned about the effect of potentially toxic residues which could contaminate the plant material (34). 

Vincent, J. B. (2000b). Elucidating a biological role for chromium at a molecular level. Accounts of Chemical Research, 33, 503—510. Vincent, J. B. (2003). The potential value and potential toxicity of chromium picolinate as a nutritional supplement, weight-loss agent and muscle development agent. Sports Medicine, 33, 213—230. 

The initial interest in selenium in medicine was caused by its potential toxicity, although the discovery of selenium as an essential element in human metabolism influenced explosively the need of selenium determinations in biological materials. In the determination of selenium in human materials it is necessary to take the various naturally occurring chemical forms of Se into consideration. When administered to humans or animals, the organic forms of the element are readily converted to various organo-selenium compounds. The available information suggest that the behaviour of selenium in man is quite similar to that in rats and other animals (Bopp et al.. 1982)... 

Every chemical substance has an LD g associated with it. It s just that we normally think of LD g values when we are talking about medicines or toxic substances. However, one should always be aware of the potential toxicity associated with substances we normally would not consider dangerous. Relatively small doses of these substances may elicit the same negative responses... 

---