What medication did you take? Was it for depression or bipolar or schizophrenia? Unfortunately, while those medications do often work well for the disorder, they do often have sexual side effects. Not for everyone but that doesn't matter since it happened to you. Have you talked to your doctor about it? You could talk to your psychiatrist that prescribed them or your primary care doctor both. I'm sure this is really frustrating. What's hard to understand here though is the drug is long gone from your system. How could it be to blame for the low libido? You've had your testosterone level checked, correct? You say that is higher than normal. Do you suffer the originating disorder that caused the need for the antipsychotic? Do you see a psychologist?