The aspirin in the AlkaSeltzer Original formula is in solution and absorbed very quickly. Hence it tends to not affect the stomach like pills do. It is the bicarb that helps with heartburn.

AlkaSeltzer was originally formulated for hangovers.

Back when I was young, there was no Tylenol, you know. Taking
something for pain, was aspirin and that was IT!
So our family used AlkaSeltzer for pain, fever, headache, since we didn't have hangovers at all. It works very very fast, and gives quick relief compared to pills.

AlkaSeltzer Cold products have other ingredients in them, antihistamines, DM and decongestants.

When I had that damaged adductor tendon in my left leg, AlkaSeltzer was the only thing that worked. Tylenol and Aleve did nothing compared to it. I think AlkaSeltzer is a wonderful product, and I get it generically for very little cost at WalMart.

Just don't overdo aspirin, as it can affect bleeding. It lowers platelets.

There is a new fast dissolve aspirin by Bayer, being advertized now, but I haven't tried it yet. So I can't compare it yet to AlkaSeltzer.