Relationship Between Allergies and Blood Pressure

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Relationship Between Allergies and Blood Pressure

Question:

Can allergies cause a rise in blood pressure?

Answer:

Allergies don't usually cause a rise in blood pressure, but medicines to treat allergies can do this.

Decongestants such as phenylephrine (Sudafed PE) or pseudoephedrine (Sudafed, Actifed and others) constrict small blood vessels. This can very commonly increase blood pressure. These decongestant ingredients are found in a large number of combination treatment products for allergy symptoms. If your favorite allergy product ends with a "D" (for "decongestant" — an example would be "Claritin-D") or if your allergy product advertises that it is a "non-drowsy formula," then it is likely that a decongestant has been added, so read the list of active ingredients closely.

It is worth considering one other way that allergy could raise blood pressure. Nasal congestion can interfere with breathing during your sleep, making it slightly more likely that episodes of sleep "apnea" might occur. With sleep apnea, a person repeatedly stops breathing. These episodes are short, but the stress of sleep apnea raises blood pressure for hours at a time. If you awaken repeatedly at night or if a sleeping partner has noticed snoring, choking sounds or gasping for air during the night, talk to your doctor.

Mary Pickett, M.D., is a lecturer for Harvard Medical School and an assistant professor of medicine at Oregon Health & Science University in Portland, OR. At OHSU, she practices general internal medicine and teaches medical residents and students.

Last updated:	July 20, 2009