Question

A novel antibiotic is under investigation for determination of safety margins. Concerns have been raised regarding potential hearing loss due to neurotoxicty. Based on early clinical trials, the median effective dose (ED50) is 10 mg/kg. Followup studies have found that median toxic dose (TD50) that is associated with hearing loss is 80 mg/kg. What is the therapeutic index for this novel antibiotic

Answer 1

Answer:

10

Explanation:

Therapeutic index determines the length of how safe a drug is by using quantitative approach. The therapeutic index is  the ratio of the median toxic dose(TD50) or the dose that produces toxicity to the to the effective dose (ED 50) of a drug. In the present study the ED 50 is calculated as 10 mg/kg and TD 50 is calculated as 80 mg/kg.

So the therapeutic index for this novel antibiotics = $\frac{median \ toxic \ dose }{median \ effective \ dose}$

$=\frac{80}{10}$

= 10