Italy — Many famous people believed to have "died" from steroids were also using recreational drugs, especially cocaine. An Italian experiment with blood platelets explains why the combination of steroids and cocaine can cause lethal strokes. "Coke" reinforces the dangerous qualities of testosterone and counteracts good ones. The researchers performed two series of tests. First, they extracted blood platelets from the blood of healthy male subjects who were not using drugs or medicines. Then they exposed the platelets to moderately high concentrations of testosterone and cocaine. For purposes of this study, ‘moderately high’ means higher than you might find in the average male, but of the same magnitude physicians have found in anabolic-androgenic steroid users. The Italian researchers used testosterone in concentrations of 750 and 1500 nanomol. Physicians have found concentrations between 100 and 200 nanomol in heavy users. Steroids can enhance platelet aggregation and cause blood clots, and coke has the same effects. But what happens when the two are combined? The figures below tell. TXB2 is a stable and inactive metabolite of thromboxane A2 (TXA2). It is produced by blood platelets and causes vasoconstriction and platelet aggregation. The figure below shows that the increased production of TXA2 actually resulted in more aggregation. LTb stands for the transparency of the samples. As a result of the aggregation the samples became more clear. Both figures tell the same story. In contrast with predicted expectations, testosterone does not make your blood clot, and neither does coke. However, according to the Italian in vitro studies the chance of a stroke occurring starts to rise when the two drugs are combined. The researchers don’t know how this works. All they know is that androgen receptors are not involved. Adding flutamide (a drug which blocks the androgen receptors) to the mixture had no effect. Testosterone also has some direct beneficial effects on the arteries. The hormone causes vasorelaxation, which lowers blood pressure, increases blood flow and diminishes the chance of strokes. The Italian researchers discovered vasoconstruction doesn’t occur in the presence of cocaine when they exposed pieces of rabbit blood vessels to the testosterone-cocaine mixture. Once again though, the Italians are not sure how this works. Adding the anti-androgen flutamide had no effect. In vitro is not in vivo. Nevertheless, the message is clear. The chances of a stroke as the result of testosterone administration alone are not very high, but the same cannot be said for cocaine and testosterone combined. Citation Togna, G., Rita, A., Graziani, M., and Franconi, M. (15 February 2003) Testosterone and cocaine: vascular toxicity of their concomitant abuse. Thrombosis Research, Volume 109, Issue 4, pp195-201. http://www.mtra.org.au/press/03/0819.html