Do you mean saltpeter?
I only know that this is something used to prevent erections. I was told that this product
was used in the millitary during war times. I don't know whether the term is soft peter or salt peter.
The term is saltpeter, also called saltpetre, but the perception that it causes impotence is largely a myth. The chemical term for saltpeter is potassium nitrate, although there is also sodium nitrate that is referred to as Peru saltpeter. It has been used for years as a critical ingredient for gunpowder and as a food preservative, such as preserved meats. It is a common misperception that it can contribute to impotence or suppress the libido and it is a legend that the military routinely added it to the food for this property, but there is no evidence for this either.