Why do I have a headache, days after an allergic reaction?

Univ. of Nev. School of Medicine, Family Medicine

Headaches can be caused by a number on things, a couple of which may be stress and sinus congestion. Seasonal allergies can cause nasal congestion. Generalized allergic reactions can cause a stress reaction, which can lead to headaches. These headaches do not always represent sinus infections and can be normal. These usually resolve with relief of the allergy symptoms.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.

Allergies

About one out of five Americans suffers from allergies. An allergy is an exaggerated response from the immune system to a substance such as dust, pollen, pet dander or mold. Other common triggers include foods such as peanuts and milk; insect bites; and certain ingredients in cosmetics and jewelry. Allergies can cause anything from rashes and hives to itchy eyes, sneezing, coughing, diarrhea, vomiting, and wheezing.

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