A 1000 mg of Vitamin C works as an antihistamine.
It reduces not only the sneezing and itching but also the prickly heat skin eruptions.
Depending on bowel tolerance - it can cause loose stools for some people - it can be taken up to three times a day.
Cold Apple Cider Vinegar dabbed on itchy skin eruptions relieves the itchiness quite quickly for this greenhorn.
An air purifier, kept running in the room, can create a safe haven for the hay fever sufferer, even with a slightly opened window. Of course, the air purifier must be designed to, besides other air pollutants, filter out pollen.