there are many many reasons to have a mild temperature elevation. as a matter of fact dependind on the time of day that you took the temperature a temp of 100 could be considered a variation of normal. the normal body temperture hovers around 99 and tends to be a bit higher in the evening; lower in the mornings. fever is usually the body's normal response to fighting of an infection (viruses like colds) or respond to inflammation. while autoimmune disorders can be on this extensive list of reasons for a mild fever it would not be high on the list. you would need to see your medical provider for a thorough medical history some diagnostic tests and a careful examination to determine if an autoimmune disorder was the underlying reason. it is not really necessary to treat a fever especially a mild one with ibuprofen or acetaminophen. remember this is a normal response and fever helps with our immune response. unless you are particularly uncomfortable a fever can be just left alone
what if acetaminophen and ibuprofen doesn't bring down my fever? . i have a possible autoimmune disorder that has not been diagnosed as of yet. i frequently get fevers that range between 99 and 101 degrees along with chills and body aches. but as of today both tylenol and motrin did not bring my temperature down until after 3 doses.