Nasal sprays like GlaxoSmithKline 's (nyse: GSK - news - people ) Flonase are also effective against nasal congestion.

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In particular, Meltzer says, a leukotriene inhibitor like Singulair could be far better at treating nasal congestion than an antihistamine like Claritin or Zyrtec.

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Symptoms of acute sinusitis include nasal congestion and obstruction, nasal discharge, tooth discomfort and facial pain or pressure that is worse when bending forward.

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These drugs, known as PDE-5 inhibitors, can cause side effects like headaches, nasal congestion and vision problems -- and they can have dangerous interactions with the heart medication nitroglycerine.

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The majority of food allergy cases -- about 80 percent -- are "cyclic, " with mild symptoms that resemble those of pollen or dust allergies: sneezing, itchy eyes, and nasal congestion, said Dr. Alpen Patel, assistant professor of otolaryngology at Emory University.

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Sinusitis describes a range of unpleasant and sometimes debilitating symptoms that include nasal and sinus inflammation, congestion, cough, runny nose, difficulty breathing, and a reduced sense of smell.

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