well let's establish a few medical facts before we delve into the issue of whether or not valacyclovir caused the symptoms you described. first of all the flu--or influenza --can only be caused by coming in contact with the influenza virus. thus taking valacylovir and going for a run cannot "cause" you to get the flu. second 'nausea' is not a symptom of influenza. the flu is a respiratory virus. it affects your nasal passages and lungs. it's true if you swallow a lot of post-nasal drip caused by the influenza virus you might get nauseated. but generally speaking the flu is a respiratory virus. it's true that nausea and headache are potential side effects of valacyclovir. however i'm not aware of fever and chills being known side effects of this drug. to be fair the most common side effects of all medications are nausea and diarrhea so i tend to consider those as 'expected' side effects. if your flu-like symptoms persist you definitely should return to your healthcare provider for further evaluation. enlarged lymph nodes should not be taken lightly. if your fever exceeds 101. 3f seek emergency medical attention. meanwhile drink a lot of fluids. it's entirely possible you coincidentally picked up a virus just as you began your course of valacyclovir. the onset of your symptoms may have nothing to do with the medication but the symptoms are worthy of being evaluated further if they don't go away within a couple of days. wishing you well! in response to the answer above i never said the valacyclovir caused the flu the specific term i used was "brought on". also a common symptom of the flue (as i found online) is vomiting. so unless people vomit without feeling nauseous i dont see how nausea isnt a symptom of the flu. thanks for your response though.
i want to know if the flu-like symptoms i'm experiencing are from the valacyclovir i was prescribed. i was prescribed valacyclovir for treatment of hsv1. i had been taking 500mg twice daily for 4 days. on day 4 i went on a 2 mile run. i noticed that my lymph nodes in my neck were somewhat swollen and tender. after sleeping for 6 hours i woke with flu symptoms. tight neck headache congestion nausea fever chills etc. i read online that these symptoms are also common side effects of the valacyclovir. is it likely that the medication in combination with the run just brought on an actual flu?