Will Nexium (esomeprazole) work in 24 hours like Prilosec? Prilosec works good but constipates me. Which one works faster bec I can't wait 3 days for Nexium (esomeprazole)

No. Both Nexium (esomeprazole) and Prilosec are proton pump inhibitors and very closely related. They take days to weeks to be fully effective. If you need relief in 24 hours you need to take an H2 blocker like Pepcid. If your doctor thinks you need.long term proton pump inhibitor to prevent GERD complications you should discuss with him and not treat yourself.
No. Nexium (esomeprazole) can take up to 30 days to fully have an effect on your symptoms. You should take it even when you are not having them if your doctor tells you that you need to be on them.