Siporex Block is a patented compound that is made up of a combination of two essential minerals: potassium and calcium. Siporex is the strongest form of natural electrolytes, which are substances that help to regulate the amount of fluids in the body. Siporex Block is a chewable tablet that can be taken to increase muscle strength, prevent cramps, and alleviate muscle pain. Siporex Block is a well-known brand of electrolytes that has been around for more than 30 years.