It's pretty scary to think that you're addicted to any drug, especially one available at any grocery store! Oprah Winfrey even devoted an entire show to people who can't live without their decongestant spray. But, fortunately, it's safe to say that you are not really addicted to it.
Doctors and scientists define addiction in different ways. Scientists call drugs addictive if they stimulate the pleasure center in your brain. Psychiatrists, on the other hand, say something is addictive if your need for it makes you do illegal, harmful things to get it. Nasal sprays don't do either of these things. They have no effect on the brain. And while you may "need" your medicine to breathe freely, you probably aren't going to hold up a bank or skip work to go buy some.
Nasal sprays or drops are sold over-the-counter under brand names like Afrin, Sinex, Neo-Synephrine, Allerest, Duramist, and Sinarest. They contain a medicine that constricts the blood vessels inside your nose. When you have a cold, the flu, or allergies, these blood vessels become swollen and dilated. This stimulates the nasal membranes to produce large amounts of mucus. Like stepping on a garden hose, constricting the blood vessels reduces the blood flow to your nostrils. The swollen vessels shrink, and this helps to dry things up.
Unfortunately, your nose can become tolerant to the decongestant's effect if you use it for too long. Tolerance in general happens because your body launches a biological counterattack against the effects of a drug. One way it does this is by increasing cellular processes and other activities that produce the opposite effect. In the case of decongestants, the body tries to dilate the nasal blood vessels. This cancels out the decongestant's effect, and the same squeeze of the bottle that brought you relief before no longer helps. You end up using more and more to get rid of your stuffy nose. And each time you sniff more decongestant, your body redoubles its efforts against the resulting constriction.
This vicious cycle continues until you can't exist without a bottle of nasal spray in hand! If you don't use it, you are stuffed up and miserable. This is called "rebound congestion." With lots of medicine on board, your nasal passages are dry, and you feel healthy. With the medicine gone, the physiological changes that your body has made reign unchecked. What happens is the exact opposite of the drug's effect! Your blood vessels swell up again, and your nasal lining fills up with mucus, and your runny nose returns.
This is why the package labeling for these drugs tells you to limit their use to three days in a row. If you don't build up tolerance to the decongestant effects, you won't get rebound congestion. And if you are tolerant, don't worry--it's not permanent. If you quit cold turkey, the changes that your body has made will eventually be reversed in a couple weeks to a month. In the meantime, your doctor may be able to give you prescription drugs to safely combat your congestion.
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