In this Article

• Introduction
• What's the difference between a controller and a reliever?
• What are antihistamines?
• How do antihistamines work?
• What are first generation antihistamines (OTCs)?
• What are second generation antihistamines (prescription)?
• What are common side effects of antihistamines?
• What are decongestants?
• How do decongestants work?
• When should I use topical decongestants?
• What are side effects of decongestants?
• What about combination antihistamine/decongestant preparations?
• Nasal Steroid Sprays
• Other nasal sprays that might help
• Tips for proper use of nasal sprays
• Nasal Allergy Medications At A Glance
• Nasal Allergy Medications Glossary
• Nasal Allergy Medications Index

What are decongestants?

Nasal stuffiness or congestion occurs as a result of swelling of the nasal membranes. Histamine opens the blood vessels and encourages fluid leakage from them, thereby causing the tissues to become "congested." This reaction reduces the space inside the nose through which we breathe and results in the typical "blocked" or stuffy nose. While antihistamines can control many symptoms of allergic rhinitis, they are not very helpful for treating nasal congestion once it has already occurred. At this point, decongestants can be a very useful addition.

How do decongestants work?

Decongestants act on a receptor on the blood vessels. The blood vessels thereby shrink, which in turn reduces the blood flow to the area and lessens the leakage of fluid into the tissues. The result is a nasal passage that feels more "open." It is important to remember that decongestants do NOT help with an itchy, sneezing, and runny nose.

Two forms of decongestants, oral and topical, are currently available. They are probably equally effective, although the topical nasal sprays or drops work more quickly (a few minutes compared to thirty minutes). Most preparations are OTC and are relatively inexpensive. As we will see later, decongestants are frequently combined with antihistamines and are sometimes combined with mucous thinners (mucolytics).

Table III: Common Decongestants

Suggested Reading by Our Doctors

• diphenhydramine, Benadryl - Explains the medication diphenhydramine (Benadryl), a drug used for the relief of nasal and non-nasal symptoms of various allergic conditions such as seasonal allergic rhinitis.
• Chronic Rhinitis and Post-Nasal Drip - Information on post nasal drip and chronic rhinitis includes symptoms such as itchy runny nose, sneezing, itchy eyes, ears, and throat, and nasal congestion.
• fluticasone propionate nasal inhaler-spray, Flonase, Veramyst - Learn about the nasal spray drug fluticasone (Flonase, Veramyst) used to treat non-allergic and allergic rhinitis and its symptoms like a stuffy and runny nose.

Read more Nasal Allergy Medications related articles »

Latest Medical News

• Scientists Zero in on Elusive 'Allergy Gene'
• Health Tip: Using Antihistamines
• Protein May Hold Key to Blocking Allergy-Induced Asthma
• Folic Acid Might Offer Allergy Relief