I have all three types of LeFeber's Critical Care powder from my vet***, but I've found its too rich for critically ill reptiles. The high nutritional content stresses their systems more than it provides nutrition. I've started using it when I need to fatten up underweight reptiles or those who are past the critical state.
My food choice for critical reptiles is simply warmed up baby food. Sweet potatoes for very ill ones and chicken and vegetables for others. Simba got his very first bit of sweet potatoes yesterday.
Using a syringe, I put some baby food in an ounce measuring glass and heat it up in the microwave for 5 seconds. I put a tiny amount (1/8 to 1/4 teaspoon) of Repashy Calcium Plus in the glass and use a toothpick to stir it in. Then I use syringes to suck up the right amount for each beardie.
Every day, I feed this mix to my two babies (Dragon and Lucky) and then I sometimes give the leftovers to another beardie. Yesterday, Jessie ate her portion right off the spoon!
I've had critically ill beardies that have done worse on Critical Care and then improved when I put them on baby food***. I think it's because Critical Care requires so much energy to digest and they don't have enough energy reserves for that.
***NOTE***-- this is my personal belief and one of two recommendations from my vet that I've chosen to ignore. He highly recommends Critical Care after a reptile is sufficiently hydrated.
The other recommendation I ignore? I let my tortoises cohabitate. Crazy, I know, but the little ones do better with friends. I realize it's a parasite spreading risk, but I monitor the situation carefully.
So if you follow me on this, you will be outside a vet's care. After 3+ years and $15,00+ of "training," I feel qualified enough to make these decisions for the reptiles in my care. Follow at your own risk. :)