Isopropyl alcohol = beer death?

I filled my airlock with 70% isopropyl rubbing alcohol which was the advice of a seasoned brewer friend even though I thought it was probably a bad idea. Well I think I was right. I am making a 5 gallon batch of stout and my yeast went crazy in the first 24 hrs. and my airlock was filled with wort. I degassed the primary and dumped the airlock and refilled it with water. I'm afraid that the entire airlock contents (up to the fill line) of rubbing alcohol got into the primary. The yeast settled down after that.

Is my beer ruined? Is it ok to drink? Will fermentation magically eliminate isopropyl?

Think about it. Your airlock was full of wort. Which means that there was enough pressure in your primary to push the wort out of the fermenter and into the airlock. So, how did the alcohol from the airlock fight against that pressure and find it's way into your wort?

Your beer is fine and quit putting that stuff in your airlock. I use starsan in the airlock. If it ends up in the wort, it's just fine. Some folks use cheap vodka.

When I used to use an airlock from the start, I filled mine with Tequila.

But I had an AMAZING explosion - and one pissed off SWMBO. Now I use a blow-off EVERY TIME I BREW for at least the first 10 days, then I switch to an airlock.

But I second that above - the pressure is blowing out - not sucking in a vacuum. I think you will be fine.

The evaporation of alcohol is what happened. It you pour it on a table it evaporates rather readily. If you have air blowing through the alcohol like you did then it evaporates rather easily even though it only has a minimal surface.

I also recommend a blow off for at least the first week. Even since switching to a 10gal fermentor I still put on a blowoff. The most recent batch I just brewed up yesterday ended up much bigger than I planned but do to increased efficiency I rolled with everything. I ended up at 6.75gal 1.107 instead of 6gal 1.094. The yeast I'm using in my experience does not make a big krausen but we'll see.