Microdosing ZEP

I am prescribed ZEP AND insurance covers the pens. At 12.5 mg. I have reached goal weight and want to microdose. I asked about the vials but apparently my insurance will not cover the vials and my provider is recommending I get it through her preferred compound pharmacy.

If I get an empty vial, can I just inject the pens into the empty vial and then microdose from there? Has anyone done this?

I have injected the pen into into a syringe and used it a small amount at a time but that means I’m using the same needle to pin that 12.5 mg at a microdose for a few weeks which I’m told is not sanitary.

Any advice is welcomed.