Search results
Results from the WOW.Com Content Network
The botulinum toxin as the most toxic substance known has an LD 50 value of 1 ng/kg, while the most non-toxic substance water has an LD 50 value of more than 90 g/kg; a difference of about 1 in 100 billion, or 11 orders of magnitude. As with all measured values that differ by many orders of magnitude, a logarithmic view is advisable.
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 ED50 is commonly used as a measure of the reasonable expectancy of a drug effect, but does not necessarily represent the dose that a clinician might use. This depends on the need for the effect, and also the toxicity. The toxicity and even the lethality of a drug can be quantified by the TD 50 and LD 50 respectively. Ideally, the effective ...
Tricyclics have a narrow therapeutic index, i.e., the therapeutic dose is close to the toxic dose. [7] Factors that increase the risk of toxicity include advancing age, cardiac status, and concomitant use of other drugs. [8] However, serum drug levels are not useful for evaluating risk of arrhythmia or seizure in tricyclic overdose. [9]
In toxicology, the median toxic dose (TD 50) of a drug or toxin is the dose at which toxicity occurs in 50% of cases. [ 1 ] : 73 The type of toxicity should be specified for this value to have meaning for practical purposes.
Examination for toxidromes, drug testing, or laboratory test may be helpful. Other laboratory test such as glucose, urea and electrolytes, paracetamol levels and salicylate levels are typically done. Negative drug-drug interactions have sometimes been misdiagnosed as an acute drug overdose, occasionally leading to the assumption of suicide. [10]
It is the minimum dose or concentration of a drug that produces a biological response in 50% of a population being studied. Median lethal dose: For either drugs or toxins, it is a toxic unit that measures the minimum dose that causes death (lethal dose) in 50% of cases. Median toxic dose
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.