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What are antihistamines?

Antihistamines are medicines that help stop allergy symptoms, such as itchy eyes, sneezing and a runny nose. Sometimes, anantihistamine can also help itchy rashes (especially hives).

Why did my doctor give me a prescription when I could buy an over-the-counter antihistimine?

Compared to over-the-counter medicines, prescriptionantihistamines are less likely to have side effects, such as drowsiness, drymouth or blurry vision. They are better for older people, children duringschool hours, and people who work with machinery or drive cars.

Can I take my prescription antihistamine with other medicines?

You shouldn’t take prescription antihistamines if you alsoare taking certain other prescription drugs, such as erythromycin (anantibiotic), itraconazole or ketoconazole. When your doctor gives you aprescription, always ask if it’s safe to use with the other medicines you’retaking. Your pharmacist can also tell you which medicines you shouldn’t takewith a prescription antihistamine. If you aren’t sure, ask the pharmacist oryour doctor before taking another medicine.

Can I share my prescription antihistamines with friends who have allergies?

No. You should never share a prescription medicine withanother person. Your doctor has examined you and has picked a medicine that isright only for your problem. Some antihistamines can cause serious side effectsif they are given to people who are taking another medicine, or who should nottake antihistamines for another reason.