Decongestants are a group of medications that are supposed to unstop the nose or reduce the nose's congestion. Our bodies are wired so that the brain thinks that normally we should breathe through our noses, not our mouths. The feeling of a stopped up nose is not an indication of a life-threatening event, however the brain detects something is wrong and sends alarm signals. Since breathing is a very fundamental function to life, the signal is very strong. We can difficulty relaxing, sleeping, or functioning with stopped up noses. If you don't believe me, just place your finger across the bottom of your nose, to prevent nasal breathing, and then breathe through your mouth instead. Within seconds, most people feel uncomfortable. As time passes, it can really bother people.
Decongestants can reduce nasal stuffiness in some people. Their downside is a tendency in some people to cause palpitations, difficulty sleeping, reduced appetite, and with long-term use a slight tendency in higher blood pressure. For me, decongestants are ctive when I have a bad cold, but I can't sleep a wink at night, so I only use them during the day and usually put up with the congestion at night.
There have been four approved oral decongestants. First, phenylpropanolamine was a commonly used ingrediant in over-the-counter (OTC) cough and cold medications until about three years ago. A medical analysis suggested that phenylpropanolamine was associated with a higher rate of strokes in women. The FDA responded by banning it http://www.fda.gov/CDER/drug/infopage/ppa/qa.htm. Second, pseudoephedrine (PSE) is used in non-prescription products, that by law must be dispensed from behind the counter at pharmacies. PSE can be used to easily and inexpensively make methaphetamine (a.k.a. "meth"), which is a dangerous and illegal street drug. The Combat Methampetamine Act of 2005 placed restrictions on the amount of pseudoephedrine and ephedrine one may purchase in a specified time period, and further requirements that these products must be stored in order to prevent theft http://www.fda.gov/cder/news/methamphetamine.htm. Almost all prescription products containing a decongestant and sold as a pill use PSE. Third,ephedrine is older than PSE and used to make PSE. Fourth, phenylephrine (PE) is used as the decongestant in OTC products because of the law described above. PE is safe and effective.
There two drugs approved to be used as a nasal spray. The medications are oxymetazoline and phenylephrine. There are many products available. The commoner names are Afrin and Neo-Synephrine. They are both very fast-acting and effective, but they have a more significant down-side. When the medications wear off, the lining of the nose and sinuses can swell up more than originally. This process is called rebound. If people use these nasal sprays more than three to five days, then the lining gets rapidly addicted to having the nasal spray used. This disease is called rhinitis medicamentosa. Because of this, most physicians and I strongly recommend nasal decongestant sprays be AVOIDED AT ALL COSTS.
If you have questions about decongestants, ask your doctor.