Can I take a decongestant pill and nasal spray at the same time?

When I use an over-the-counter decongestant nasal spray, like Afrin, can I also take decongestant pills? What should I watch out for?

There is probably no need to take them at the same time, say our pharmacist consultants. You don't need to—and, if you do take both, you might get an overload of decongestant. But when suffering from a cold, it may be a good idea to use a spray for the first few days, and then switch to an oral decongestant, if it's still needed. (If congestion is caused by allergies, your best, first bet is an over-the-counter antihistamine.)

Nasal sprays are topical decongestants. The active ingredient works within minutes to shrink swollen blood vessels in your nasal passages, helping you breathe more easily. Sprays containing oxymetazoline, such as Afrin, Dristan, or Vicks Sinex, can relieve congestion for up to 12 hours, while sprays containing phenylephrine, like Neo-Synephrine, last up to four hours.

At recommended doses, they're usually not absorbed into the bloodstream the way that oral medications are, but occasionally they can—say, if you took more than the recommended dose, or you tilted your head back while spraying your nostrils allowing some of the spray to enter your throat. (This is less apt to happen if you keep your head upright.)

Because of that possibility, those who have enlarged prostate, glaucoma, heart disease, high blood pressure, or thyroid disease should check with their doctor or pharmacist before using nasal sprays at all because all decongestants, including sprays, can worsen these conditions. If you experience insomnia, dizziness, weakness, tremor or an irregular heartbeat contact your doctor right away.

Also, nasal sprays are usually only recommended for a maximum of three days' use. When used for a longer period of time, you could face rebound congestion—short-term, severe congestion as the medication effect wears off. "When you stop using the spray, the vessels in your nose that have been held in check begin to swell, making you feel congested," says pharmacist Beverly Schaefer, co-owner of Katterman's Pharmacy in Seattle. "It takes one to three days to get back to normal."

To avoid rebound congestion, try taking the oxymetazoline nasal drops or sprays for the first three days, then make a switch to pseudoephedrine pills (Sudafed and generic). Be aware too that exceeding the recommended dosage of pseudoephedrine can cause nervousness, dizziness or sleeplessness. To get pseudoephedrine, you'll have to ask the pharmacist since it's no longer carried on pharmacy shelves--only behind the counter. However, you don't need a prescription.

For nasal congestion relief, don't rule out nondrug treatments. For example, studies show that a saltwater rinse for the nose can also help. And, believe it or not, chicken soup can help you feel better. A least one study has shown it prevented a build-up of white blood cells, which trigger the inflammatory response that makes you feel so poorly when you have a cold.

If you're a frequent nasal-spray user, ask your doctor what might be the cause of your congestion, rather than depending on prolonged use of the drug and risking the rebound effect. There could be an underlying problem, such as a sinus infection or allergies. Your doctor may prescribe an antihistamine or steroid nasal spray that's more appropriate for a chronic condition.

Have a medication question or pharmacy concern? Our pharmacist consultants can help. E-mail us at: crbestbuydrugs@cu.consumer.org and include "PHARMACY QUESTION" in the Subject line.

—Lisa Fields