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.
How long do I have to wait to take Ibuprofen after I take Excedrin Migraine? I took one Excedrin migraine this morning for a sinus headache and it did not do the trick. The usual dose is two though, but I am sensitive to caffeine so I only took one. (250 MG Acetamiophen, 250 MG NSAID Aspirin), How many hours should I wait until I take 400MG of ibuprofen, my usual dose for sinus headaches? I would appreciate any help or advice you have to offer.