Besides an intermittent cough, I have been fighting a fever since Friday night. It reached a high of 104.2 and I took Ibuprofen and drank lots of liquids. Within a half hour, my temperature dropped to 102.9. Trying to let the fever kill the infections, I carefully monitored my temperature on Saturday. It hovered between 102.5 and 103. I had to take some more IBUprofen early Saturday night. After the medicine had wore off, my temperature then dropped to 101.7 on Sunday and 100.5 Sunday night. It was 99.8 this morning. It is back to 100.5. I can be patient in letting the fever do its job, if that is the right thing. My question, what is this? And how long should it last?