Allergic Rhinitis | Antihistamines


What are antihistamines?

Antihistamines are medicines that help stop allergy symptoms, such as itchy eyes, sneezing and a runny nose. Sometimes, an antihistamine 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, prescription antihistamines are less likely to have side effects, such as drowsiness, dry mouth or blurry vision. They are better for older people, children during school 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 also are taking certain other prescription drugs, such as erythromycin (an antibiotic), itraconazole or ketoconazole. When your doctor gives you a prescription, always ask if it's safe to use with the other medicines you're taking. Your pharmacist can also tell you which medicines you shouldn't take with a prescription antihistamine. If you aren't sure, ask the pharmacist or your doctor before taking another medicine.

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

No. You should never share a prescription medicine with another person. Your doctor has examined you and has picked a medicine that is right only for your problem. Some antihistamines can cause serious side effects if they are given to people who are taking another medicine, or who should not take antihistamines for another reason.

Written by editorial staff

Reviewed/Updated: 04/14
Created: 09/00