Thank you for coming back online.
The symptoms you have described of having rash with red dots that started where your underwear hurt & now spreading to all over body after 1 day of your getting of flu vaccine,can most likely be due to hypersensitivity/side effect of flu vaccine.
A hypersensitivity reaction (similar to an allergy) occurs in the skin, causing inflammation. The inflammation causes the skin to become reddish & itchy.
The following will help you greatly:Take tablet benadryl once a day.Apply cream containing hydrocortisone.
If the area is large then apply Calamine lotion.This will reduce the rashes & itching.All these medications are available at your counter without any prescription.
If still after this,the symptoms persists,then you need to make an appointment with your doctor as prescription oral medications like anti histamine will then be required accordingly.Usually & most likely,the symptoms gets subside with these treatments.
Hope this helped
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