Fever may cause high blood pressure because the heart rate increases when you have a fever, and an increase in heart rate can lead to an increase in blood pressure. Fever is most often caused by bacterial or viral invasion, and medication can only be taken after the cause is understood, but regular medication can easily lead to a low immunity and susceptibility to illness. Therefore, it is recommended to use dietary therapy for treatment. You can take 25g each of walnuts, white onion and ginger, and 15g of tea. Pound the walnuts, white onion and ginger together, put them in a casserole with 250ml of water and decoct them with the tea, remove the residue and take them all at once, then cover them with bed rest, which can help reduce fever. Always remember to drink more water, forbid to eat some spicy and stimulating food, and eat more light, vitamin-rich food. If the condition continues to deteriorate and the fever does not subside, it is recommended to go to the hospital promptly and get symptomatic treatment according to the doctor’s advice.