Q&A: Can Barometric Pressure Cause Headaches and Other Discomforts?

Q. What effect does the barometric pressure have on humans? Can it cause headaches and other discomforts?

A. Differences in air pressure because of the weather or changes in altitude can have noticeable effects on the human body, though some people are more sensitive than others.

Low barometric pressure can cause headaches by creating a pressure difference between the surrounding atmosphere and the sinuses, which are filled with air, said Dr. Matthew Fink, neurologist in chief at NewYork-Presbyterian Hospital/Weill Cornell Medical Center. That leads to distended sinuses, especially if there is any congestion or blockage.

"The same thing can happen with joints in people who have arthritis," Dr. Fink said, with the low pressure associated with a coming storm aggravating joint pains in some.

"High barometric pressure does not usually cause a problem, unless it is extreme," he said. For example, water pressure can cause serious problems for a scuba diver because nitrogen dissolves in the blood when it is under pressure for some time. When the pressure is released as a diver ascends too quickly, the gas expands into bubbles; the resulting organic distress, often called the bends, can be fatal.

One of the most noticeable effects of shifting air pressure occurs when a plane changes altitude rapidly. As expanding or contracting air in the middle ear equalizes its pressure with the surrounding atmosphere, ear popping and pain are common.

question@nytimes.com

This article has been revised to reflect the following correction:

Correction: July 4, 2013

The answer in the Q&A column on Tuesday about the effects of barometric pressure on humans misidentified the part of the ear where the expansion or contraction of air as altitude changes can cause popping and pain. It is the middle ear, not the inner ear.