Your pain is probably coming from your sinuses, and it's the change in atmospheric pressure when the plane takes off or lands that's probably triggering your throbbing headaches.

The sinuses are a series of holes or caves in the bones in the middle of the skull. They are connected by narrow passages to your middle ears, nose and the back of the throat. If these passages become blocked or swollen, air can get trapped within the sinuses. Differences in pressure between the air in the sinuses and the air in the cabin of the plane (which is the same as atmospheric pressure) can then cause the sinuses to shrink or expand, which in turn causes a sense of pressure, fullness, or even throbbing pain. Many people experience "popping" in the ears for exactly the same reason. (The technical term for this condition is barotrauma.

It's also possible that the pain is not coming from the sinuses, but that changes in atmospheric pressure are triggering a migraine headache. Many people complain of "sinus" headaches, although it's unusual that the sinuses themselves cause head pain. Instead, many experts think that the typical "sinus" headache is a migraine or tension-type headache that's been triggered by any number of sinus conditions, such as allergies or sinus infections.

Is there anything to be done about headaches triggered during air travel? Here are a few suggestions:

• Use a nasal decongestant such as oxymetazoline (Afrin) nasal spray about 30 minutes before your flight. This should help to open the sinus passages and prevent pressure buildup. A pill decongestant such as pseudoephedrine (Sudafed) also can help, although this type of medication should be avoided by people with high blood pressure or heart conditions.
  
  
• If you have chronic sinus problems, an antihistamine pill (such as Claritin or Chlor-Trimeton) or a prescription steroid nasal spray may be helpful. Rarely, the symptoms you describe can be caused by nasal polyps or more serious types of sinus blockage.
  
  
• If decongestants don't work, you can try an over-the-counter pain reliever such as ibuprofen (Advil, Motrin), naproxen (Aleve) or acetaminophen (Tylenol). Take the pain reliever at the first sign of a headache, or even before the headache starts.
  
  
• If over-the-counter pain relievers don't work, you can speak to your doctor about a prescription headache medication.