If a plate with oceanic lithosphere meets another plate, the dense oceanic lithosphere dives beneath the other plate and sinks into the mantle: this process is called subduction. The sinking oceanic lithosphere drags the rest of the tectonic plate: this is the main cause of plate motion.
You may notice a decrease in symptoms during the build-up phase, but it may take as long as 12 months on the maintenance dose to notice an improvement. If allergy shots are successful, maintenance treatment is generally continued for three to five years.
A cortisone shot typically starts providing relief from symptoms within 48 to 72 hours, according to About.com. Cortisone shots relieve pain by reducing inflammation. Inflammation begins to subside immediately after the shot although significant pain relief can take a few days to a few weeks. Continue Reading.