Search results
Results From The WOW.Com Content Network
This type of adverse effect that results from pharmaceutical drug exposure is commonly due to interactions of the drug with its intended target. In this case, both the therapeutic and toxic targets are the same. To avoid toxicity during treatment, many times the drug needs to be changed to target a different aspect of the illness or symptoms.
Even less safe are drugs such as digoxin, a cardiac glycoside; its therapeutic index is approximately 2:1. [12] Other examples of drugs with a narrow therapeutic range, which may require drug monitoring both to achieve therapeutic levels and to minimize toxicity, include dimercaprol, theophylline, warfarin and lithium carbonate.
The median toxic dose encompasses the category of toxicity that is greater than half maximum effective concentration (ED 50) but less than the median lethal dose (LD 50). However, for some highly potent toxins (ex. lofentanil , botulinum toxin ) the difference between the ED 50 and TD 50 is so minute that the values assigned to them may be ...
The mechanism of action is a crucial factor in determining effect and toxicity of the drug, taking in consideration the pharmacokinetic (PK) factors. [12] The sort and extent of altered cellular physiology will depend on the combination of the drug's presence (as established by pharmacokinetic (PK) studies) and/or its mechanism and duration of ...
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. [1] Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell (cytotoxicity) or an organ such as the liver (hepatotoxicity).
Negative values of the decimal logarithm of the median lethal dose LD 50 (−log 10 (LD 50)) on a linearized toxicity scale encompassing 11 orders of magnitude. Water occupies the lowest toxicity position (1) while the toxicity scale is dominated by the botulinum toxin (12). [107] The LD 50 values have a very wide range.
Type A: augmented pharmacological effects, which are dose-dependent and predictable [5]; Type A reactions, which constitute approximately 80% of adverse drug reactions, are usually a consequence of the drug's primary pharmacological effect (e.g., bleeding when using the anticoagulant warfarin) or a low therapeutic index of the drug (e.g., nausea from digoxin), and they are therefore predictable.
Both pharmacology and toxicology are scientific disciplines that focus on understanding the properties and actions of chemicals. [23] However, pharmacology emphasizes the therapeutic effects of chemicals, usually drugs or compounds that could become drugs, whereas toxicology is the study of chemical's adverse effects and risk assessment. [23]