Yes, perhaps you need to change medications in order to fix the concentration problems. Of course, the problem is that if your current cocktail is effective and keeps you stable, then switching medications may throw you for a loop. So that's a risk you have to consider.

Besides changing medications, you can always ask someone to slow down when talking or ask them to repeat what they just said. Most people don't think twice about that stuff because everyone at some point asks for someone to slow down with talking or ask them to repeat some things they just said, so asking them to do one of those two things isn't that unreasonable. (I'm not saying you think it's unreasonable, but I'm just making a statement.)

Also, I don't know if this applies to you, but I have a desk job, and whenever people at work tell me something, I ask for them to send it as a text message or an email. So if you have a job -- or just friends who you like to text -- just politely say, "Can you send me an email or text so that I don't forget?" I haven't run into a single person who's gotten upset or bothered by the fact I asked them to send me an email or text. They usually say, "oh, sure. Not a problem."