Erectile dysfunction

So my husband just informed me that he thinks he has this. Right now we pretty much have a nonexistent sex life. I was just starting to think he was not interested in me. Well it turns out he went to the doctor for it(I had no clue) and got medicine, but he said he stopped taking it because it made him feel super angry. He said they told him he had low testosterone. What should he do now? I have no clue other than to go back to the doctor for different meds? Any advice ladies...