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Male contraceptive medication will have poison in its composition
Last reviewed: 02.07.2025
Scientists are already completing work on creating the first male contraceptives. But what is noteworthy is that one of the components of such pills will be an exotic plant poisonous substance, which in ancient times was used to treat spears and arrows.
American specialists suggest that a natural extract called "ouabain" (in medicine it is more familiar as "g-strophanthin") can block not only cardiac activity, but also sperm activity.
Studies on rodents have shown that a slightly modified form of the poisonous substance significantly slows down spermatozoa, and does not harm the health of males.
Scientists have taken on the solution to this problem for a reason. It has always been believed that contraceptives can only be intended for the female half of humanity. Men can only use condoms or a more radical remedy - vasectomy. Experts considered this unfair, and in 2016 they began the first experiments. Today, scientists are confident that the ancient hunting poison can become the first contraceptive in the form of pills for men.
The strophanthin in question is isolated from exotic African plants. Ouabain has an exceptionally powerful effect and immediately affects the contractility of the myocardium. Modern medicine allows the use of minimal doses of strophanthin to correct the heart's function when it is insufficient. Although today there are safer and more effective drugs.
What did the scientists discover? The main proteins that are suppressed by ouabain are localized in the myocardium. However, their analogues are also present in active spermatozoa, providing their motor ability. This means that the poison can immobilize them. But how to use the drug if, simultaneously with the spermatozoa, it also affects the heart muscle?
Long-term work led to the desired result: specialists modified ouabain, directing its action exclusively to suppressing the mobility of spermatozoa.
Several varieties of the drug have already been tested in the laboratory. This made it possible to find out the following: if the lactone group in the molecule is replaced with a triazole group, the lethal substance will turn into a safe contraceptive.
Experiments on rodents have proven that the new substance is selective and affects only the motor activity of spermatozoa, thereby reducing the chances of reproduction.
The new modified poison is not toxic to the body, and its effect is completely reversible. That is, after the end of taking the contraceptive drug, subsequent generations of spermatozoa do not suffer.
The researchers will soon announce full-scale clinical trials, the results of which will allow them to say with certainty whether the new pills will be widely used as a male contraceptive.
The study's leader, Gunda Georg, representing the University of Minnesota Medical School (Minneapolis), shared details of the study in an issue of the Journal of Medicinal Chemistry.
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