Re: Correcting for salt vs. base
It depends on how the dose is reported, Dennis. In many cases salts are dosed using the quantity of based delivered. The clearest example is fosphenytoin, which is dosed in phenytoin equivalents, and the drug measured in plasma is phenytoin. However, if the dose delivered is reported as the amount of salt, then I would decrease the AMT by a multiplier S which should be a known constant.
Paul
Quoted reply history
On 3/26/2014 7:57 AM, Fisher Dennis wrote:
> Colleagues
>
> I have been troubled by a minor issue for some time. Consider the following situation:
>
> Dose is reported in mg salt
> Cp is reported in ng/ml base
>
> Since CL is dose / AUC and AUC is merely the integral of Cp vs. time, in theory, dose should be converted to mg base (or concentration to ng/ml salt).
>
> However, I am not sure if everyone does that.
>
> In fact, an argument against it is that not doing the conversion permits one to relate the administered dose (which is usually based on salt) to a Cp value (usually based on base).
>
> I am interested to hear what approach people use.
>
> Dennis
>
> Dennis Fisher MD
> P < (The "P Less Than" Company)
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