Susan,

 

I don't know  the context of the discussion on the Addison's Board, but here are just a couple of more thoughts regarding dosaging. If a change is being considered from HC to dex (or vice versa), I think it is wisest to figure dose based on recommended amounts for that particular drug, rather than trying to mathematically equate one to the other.  Unfortunately, it (converting from one med to another) doesn't appear to be an exact science and mistakes are easily made, so you'll probably spin your wheels less if you start from scratch. 

 

Dex is usually dosed around 0.25 mg/meter squared/day, but average amounts vary between 0.24 and 0.33 mg/meter squared/day.  From the paper by Drs. Rivkees and Crawford: Dexamethasone was given in a dilute elixir preparation to offer better titration of dosage. The morning doses ranged between 0.24-0.33 mg/m2/d.  Five patients did require lower doses of 0.04-0.17mg/m2/d. 

 

As has been discussed here before, "meter squared" ("m2") refers to a person's body surface area, a number based on individual height and weight.  There are several websites that will figure this out for you---all you have to do is fill in the blanks.  The one I use (thanks to Chris D.) is at http://medicine.ucsd.edu/cystinosis.bodysurf.htm .  On Danette's CAH board at http://www.cahourstories.net/forum/wwwboard.html , Joan W. gives another website to figure BSA, and also provides a good example of how to to do this.  Look for her post of 05/08/01 "Re. Undersuppression to Donna," under Donna's original thread "Undersuppression"  (about halfway down the page.)

 

Because of dex's high potency, it is very important to closely titrate doses in order to maintain tight control and avoid both under- and oversuppression.  Drs. Rivkees and Crawford use the liquid dex (elixir) exclusively, to treat their CAH patients, and also instruct them to measure using a medication syringe, which forces out all the air bubbles.  Doing it this way makes it possible to get down to amounts as small as 0.01 mg. of dex---roughly equivalent to breaking a 5 mg. HC pill into 6 equal pieces or a 0.25 mg. dex pill into 25 equal pieces!!!!!

 

Liquid dex apparently comes in different potencies and, again, in order to achieve tight control, a "dilute" preparation, with concentration "0.1 mg/1 ml"---which can also be stated on the label as "0.5 mg/5ml"---is recommended.  It comes under the brand name "Decadron,"  but generics are also produced by a number of different pharmaceutical companies, including Alpharma and Marvin Grove.  Dex elixir is also very inexpensive. With our insurance, we have a 20% copay for drugs.  At my son's current dose, a bottle of the generic, which lasts 2-3 months, costs us less than $2.00!

 

Again, hope this helps and pls. let me know if any of this is unclear! 

 

P. S.  I'm glad to read, from one of your recent posts (I'm not sure on which board---Danette's or LOCAH, I think?) that your new dose of dex seems to be working out well for you!!