In Mombasa we meet Eames' chemist, Yusuf. He's got some pretty heavy sedatives (and a cute cat).
We see that a lot of elderly people come to him every day to dream—or to be woken up. Because, as the wise old man says, the dream has become their reality.
Again, we see Cobb visibly shaken by meeting Mal (who we've now confirmed is dead). This seems like a problem that's not going to go away.