What are antihistamines?

Antihistamines are medicines that help stop allergy symptoms such as itchy eyes, sneezing and a runny nose. Sometimes, itchy rashes (especially hives) may also be helped by an antihistamine.

Why did my doctor give me a prescription when I can buy it "over-the-counter"?

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 (brand name: Sporanox) or ketoconazole (brand name: Nizoral). 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.

More Information

For more information talk to your doctor.


Written by editorial staff.

American Academy of Family Physicians

Reviewed/Updated: 03/07
Created: 09/00