Has more side effects than Allegra since it has pseudoephedrine in it. The antihistamine (fexofenadine) can cause dizziness, drowsiness, dry eyes/mouth, and constipation. The decongestant (pseudoephedrine) can make your blood pressure higher and can make it harder to sleep.
Food preservatives (or additives) contained in certain foods can trigger headaches. Nitrates and nitrites are additives in: 1  Hot dogs. 2  Ham. 3  Sausage. 4  Bacon. 5  Lunch meats and deli-style meats.6  Pepperoni.7  Other cured or processed meats. 8  Some heart medicines.ood preservatives (or additives) contained in certain foods can trigger headaches. Nitrates and nitrites are additives in: 1  Hot dogs. 2  Ham. 3  Sausage. 4  Bacon. 5  Lunch meats and deli-style meats. 6  Pepperoni. 7  Other cured or processed meats.
Nitrate Allergy Symptoms. Nitrate is the chemical compound found in various foods. It is used as a preservative for foods. Nitrate allergy symptoms are found in some people by eating processed foods. The people who are sensitive to this chemical might suffer serious headaches to migraines due to nitrate allergy.