Although it's still not clearly understood how, exactly, amyl works, what happens when it does sure is.
Once inhaled, it triggers a quick jump in heart rate and drop in blood pressure and relaxes smooth muscle tissue. At the same time, it shuts off oxygen to the inner brain, producing a sudden, intense weakness and dizziness lasting 2-3 minutes. Sweating and flushing may also occur.
Still, if you need it, amyl nitrite is good medicine -- or was, before it was replaced by newer drugs. In fact, the drug was so effective -- and so relatively safe -- that it was sold over the counter for years, packaged in small mesh-covered vials.
As time passed, though, amyl eventually found a larger market, one with healthy hearts -- particularly once word spread that the drug seemed to intensify sexual orgasm. Users dubbed the vials "poppers" and "snappers," due to the sound they made when crushed, and snapped up what they could from pharmacies.
And even though amyl nitrite isn't an aphrodisiac and doesn't help in treating sexual problems, it quickly gained a reputation as a "love drug," especially among gay men.  
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