I've never donated blood, but I'm assuming there are questions about drug use before they take your blood.
If you tell them you are using testosterone without a prescription, will they deny you?
Is this the one instance where you might be better off not mentioning it?
They will defer you for any injectable drug use including steroids. It's built into the questionnaire to weed out individuals with "high risk" activities and life styles. Just google American Red Cross donation deferral list or something along those lines.
im the sh!t, even your girlfriend can smell it
I think as long as anything you're doing is by doctors orders/prescription (ie TRT), you can donate. I just don't even go through the trouble of going into medical records, making phone calls to drs, etc.
My regular doctor (not the trt doc) got me started donating every 3 months last year. She told me it didn't matter that I was on injections, the blood was fine as long as the hemoglobin levels were in range. A few weeks ago I went in to donate and my hemoglobin level was 18.9. The clinic told me that was the highest level they would accept. Went back to my regular doctor and she gave me a script for donating every two weeks until my levels come down. The script she wrote had "testosterone replacement" on it as the reason for the high hemoglobin level. I donated again last Friday and they basically told me the blood was fine if the hemoglobin levels were not so high. They trashed the pint I gave them but said my donation could be used again when the levels are back in range.