"Do you know if he took anything right before this happened?," the dispatcher asked.
"Here's what I got. They just handed me something called Reload 72-hours strong sexual performance enhancer," the caller replied.
That drug — Reload — contains sildenafil, which is the same ingredient found in Viagra and treats erectile dysfunction. But unlike Viagra, Reload doesn't have that ingredient on the label. So why is this an issue?
Sildenafil can interact with nitrates in certain prescription drugs, causing a dangerous drop in blood pressure. Men with diabetes, high blood pressure, high cholesterol or heart disease often take medications that have nitrates.
We spoke with a physician who explained that sildenafil affects veins like this: If you connect a 1-inch-diameter hose to a faucet and then turn the water on, the water will shoot out of the hose. But if you take that same faucet and connect it to a 6-inch-diameter hose, the water will come out at a dribble because the pressure drops.
So when you take sildenafil, it causes your once narrow blood vessels to widen, making your blood pressure tank. Nitrates essentially have the same effect, so, when taken together, the resulting drop is even stronger.
But here's where this gets really interesting. Cocaine, which Odom had reportedly been taking, has the opposite effect of sildenafil: It makes blood vessels constrict. So taken together, the two would, in theory, offset each other somewhat, according to the physician.
While it's unclear if Odom had other illicit drugs in his system when he collapsed, it could have been a perfect storm when we consider a few other factors.
Another factor is the environment. The average high this past weekend in Crystal, Nevada — where Dennis Hof's Love Ranch South is located — was a hot and dry 91 degrees. If Odom was dehydrated, that would have made his blood pressure problems worse.
We obviously won't know the true cause of Odom's collapse until the toxicology report is completed and released. As of Thursday afternoon, he remains in critical condition on life support at Sunrise Hospital in Las Vegas.
This video includes images from Getty Images.