Injectables rated IP and other Questions

I've got a couple of things going on in my research and want to make sure that I've got everything optimized.

First off, HCG is involved for PCT. The HCG is being used SQ, and I have usually had discomfort with SQ peptides (not red, but a sore spot for 24-48 hrs).

Secondly, I have dosed 100mg of hydrocordisone due to some groin issues extending down the semitendinosus muscle. I dosed IV as I prefer to dose IV when possible. I have only the single dose of the hydro, but I have another cortico that is rated IP. My understanding is that IP is a step beyond IV and is therefore acceptably dosed this way.

With the HCG being in the mix, I want to minimize the chance of a small infection from the shots. What would be the optimal dosing of corticos to minimize the suppressed immune system? Is this something that I should be worried about? Will simply adding echinecea be enough?

Oh, and what I have now is betamethasone.

In the end, I'm going to use it and would prefer IV unless someone know strongly why I should not. There is no acetate ester in my solution.