I hope they got the meds right now. My doctor did say that it is often hard to find the right anti nausea meds so it could be rough for a bit. There are several drugs to go through so if they dont have the right one now, press for a change.
I have also been prescribed Primperan (Metoclopramide). I am supposed to take that IF I vomit to help prevent more. It somehow works differently than the anti nausea meds you take before you vomit the first time. So you may want to ask about that. My primeran is a suppository so it makes sure you cant vomit it up and you get the full dose. I call them my little torpedos.
Try to keep your brother hydrated while he is sick. Pedialite and sports drinks are good because they keep your body's electrolytes up. In fact, my best friend (a pediatric oncologist) said that we should all be drinking those for a couple of days after an infusion.
When I was sick, sick, sick, I was also eating baby food as it was easier to digest so I knew I was getting some nutrients before the unevitable happened.
Hope your brother feels better today.
Cancer is a word, not a sentence.
36 year old patient with buckets of hope