The electromagnetic (EM) spectrum is the range of all types of EM radiation. Radiation is energy that travels and spreads out as it goes  the visible light that comes from a lamp in your house and the radio waves that come from a radio station are two types of electromagnetic radiation.
According to my doctor, 4 hours. You can switch them up. Take acetaminophen, (Tylenol), then wait 4 hours and take Ibuprofen, wait another 4 hours and take acetaminophen and sâ¦o on.
My son had high fevers and I gave him advil, then 2-3 hours later tylenol, then advil 3 hours after that, then tylenol 2 hours later.....back and forth. A doctor recommended this because my son had seizures with a high fever.Read the label. If it says tylenol ever 4 hours then that's what you do.y son had high fevers and I gave him advil, then 2-3 hours later tylenol, then advil 3 hours after that, then tylenol 2 hours later.....back and forth. A doctor recommended this because my son had seizures with a high fever.