The milligram quantity is usually quoted on the label in milligrams or
micrograms in addition to the IU.
Dennis Brownridge wrote:
>
> I guess my discomfort with IU is that it seems to be a completely arbitrary
> unit that tells me absolutely nothing about how much of the stuff I am
> actually getting, or even what that stuff is. 1 IU of one nutrient doesn't
> seem to have any relation at all to 1 IU of another nutrient. One might
> measure in milligrams while the other measures in nanograms, a million times
> less. Would it be possible to give doses in masses "equivalent to" some
> standard preparation, with the understanding that the actual mass might be
> different? For example, could they give Vit. A doses in µg of Retinol
> equivalents or something? Perhaps abbreviated as Vit. A (RE) 1 µg. We do
> this with radiation (the sievert, an SI unit, which measures the dose
> "equivalent to" 1 J/kg of some standard) and it seems to make more sense to
> me. But note that I am not suggesting we invent new SI units for vitamins!
>
> > -----Original Message-----
> > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On
> > Behalf Of Scott Clauss
> > Sent: 2000 December 4 Monday 12:42
> > To: U.S. Metric Association
> > Subject: [USMA:9520] Re: International Unit
> >
> >
> > See below. International unit dosing is the only way I see to
> > sell some of
> > these compound classes without ridiculously expensive and
> > needless separtion
> > and clean-up procedures.
> >
> > Scott C.
> >
> > > -----Original Message-----
> > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On
> > > Behalf Of Dennis Brownridge
> > > Sent: Saturday, December 02, 2000 3:22 PM
> > > To: U.S. Metric Association
> > > Subject: [USMA:9505] Re: International Unit
> > >
> > >
> > > Rowlett's dictionary of units reports that, for "standard
> > preparations," 1
> > > IU =
> > >
> > > 0.3 µg of vitamin A
> >
> > Vitamin A occurs in two principal forms in nature: retinol, which is found
> > only in animal sources, and certain carotenoids, the best known
> > of which is
> > beta-carotene. beta-Carotene can be converted to retinol in the
> > body. So if
> > you were selling pure retinol you could probably sell by the
> > mg/dose, but if
> > you are selling a mixture of carotenoids, each with its own convertion to
> > retinol efficiency you wouldn't really be able to sell by mass/dose.
> >
> > > 50 µg of vitamin C
> >
> > Is one compound, ascorbic acid, so is usually sold as mg/tablet.
> >
> > > 25 ng of vitamin D
> >
> > Vitamin D is the generic name for a group of steroid-like substances with
> > anti-rachitic activity. It is found only in animals. The two most
> > prominent
> > members of this group are ergocalciferol (vitamin D2) and cholecalciferol
> > (vitamin D3).
> >
> > > 0.66 mg of vitamin E
> >
> > Vitamin E is the collective name for various tocopherols and tocotrienols.
> > The most active form is of vitamin E is alpha-tocopherol.
> >
> > > 45.5 µg of insulin
> >
> > Is a large protein hormone made these days by fermentation with
> > bioengineered bacteria or yeasts, so in addition to those 45.5
> > µg, activity
> > also depends on whether some of the hormone has lost its structural
> > integrity during clean up, and what other inactive protein
> > fragments may be
> > present. Weighing the extract would not tell that. They may use diabetic
> > animals to test the response and establish the activity of a
> > batch, and this
> > would be given in international units/dose.
> >
> > > 0.6 µg penicillin
> >
> > Is an antibiotic of specific structure, so should be sold by mg/dose. The
> > structure has been tweeked chemically to counteract bacterial resisitance,
> > but these are given different names, eg Ampicillin, Amoxicillin, etc.
> >
> >
--
Paul Trusten, R.Ph.
3609 Caldera Boulevard, Apt. 122
Midland TX 79707-2872 USA
[EMAIL PROTECTED]
"No one from the Audubon Society has yet documented the
finding of a modified barium swallow."
--Byrd Ona Wyng, Forensic Ornithologist
"Free Billy Rubin!" ---Medical Technologists' protest cry
