Introduction

Although they are the cornerstone of allergy treatment, avoidance measures are not always enough to manage all of the symptoms. When the symptoms of nasal allergies are mild or intermittent, antihistamines with or without decongestants can help. Very often, some relief can be found in taking over-the-counter (OTC) drugs and this is usually the first step an allergy sufferer will take. Self-medication, though, is frequently inadequate since OTC drugs cannot adequately treat the inflammation that develops in the nose. At this stage, anti-inflammatory medications are required, usually in the form of intra- nasal steroid sprays (sprayed into the nose).

The combination of an antihistamine (with or without a decongestant) and a topical nasal steroid spray will usually afford good relief with minimal side effects. The addition of ipratropium bromide nasal spray (Atrovent - an anticholinergic medication) is also very effective for a runny nose that has been unresponsive to prior treatments. Let's look at these medications in more detail to understand their role in the treatment of nasal allergy.

What's the difference between a controller and a reliever?

Throughout this section on allergy management, we will be referring to the various treatments as "controllers" or "relievers" of symptoms. Controllers are used to prevent symptoms by interfering with the underlying causes of the inflammatory response or the actions of chemical mediators. Examples of controllers include:

• Drugs that block the attachment of histamine to special receptors on cells (e.g., antihistamines);
• Drugs that prevent mast cells from releasing chemicals (e.g., Cromolyn); and,
• Drugs that prevent or reduce inflammation that arises from an allergic reaction (e.g., steroids).

Other medications, called relievers, are used to alleviate symptoms without affecting the inflammation. They are also called "rescue" medications and in general provide only temporary relief. Relievers should only be used alone for mild or intermittent symptoms. Examples include:

• Drugs that narrow (constrict) the blood vessels in the nasal membranes, thereby helping "shrink" swollen tissues and relieve congestion (e.g., decongestants); and
• Drugs that reduce mucous production by blocking the nerve supply to the mucous glands (e.g., anticholinergics).

What are antihistamines?

Antihistamines are one of the most commonly used OTC and prescribed medications. They are beneficial for nasal and eye allergies, eczema, and hives but tend not to be effective in asthma.

Antihistamine is a combination of two words. "Anti-" means against, and "histamine" is a naturally occurring chemical that is released by the mast cells.

How do antihistamines work?

Human cells have three different types of histamine receptors (H1, H2, and H3). Histamine works by attaching itself to these receptors on the surface of cells and thereby causing its effects. It is mainly through the H1 receptors that histamine causes symptoms of allergy. Antihistamines act by attaching to these same H1 receptor sites, thereby preventing histamine from binding to them. This action prevents the histamine from causing allergic symptoms.

Histamines can cause swelling, sneezing, itching (nose, throat, roof of mouth), and a runny nose through the nostrils or down the back of the throat (post-nasal drip). Antihistamines are effective in treating the sneezing, running, and itching. They usually begin working between 30 to 60 minutes after being taken. However, histamine is only one of the many chemicals involved in the allergic reaction, which explains why relief from antihistamines is usually only partial.

Allergy Fact

Bovet and Straub at the Pasteur Institute discovered the first antihistamine in 1937. It was too weak, however, and caused many side effects. In 1942, phenobenzamin (Antegan) was the first antihistamine used to treat allergies. Within a few years, diphenhydramine (Benadryl) and tripelennamine (PBZ) were formulated.

What are first generation antihistamines (OTCs)?

Many of the older antihistamines are now available OTC. Many different preparations are available, and are derived from six separate chemical classes. Although these inexpensive OTC drugs are helpful in controlling milder symptoms, they also cause various side effects. Drowsiness and reduced mental alertness are particularly common (seen in up to 50% of those taking the medications). Cells that line the blood vessels in the brain regulate which chemicals can enter the brain. These cells are referred to as the blood brain barrier. The reason these drugs induce sleepiness is that they are able to cross the blood brain barrier.

Table I: Common First Generation Antihistamines

Generic Name	Brand Name
diphenhydramine	Benadryl
chlorpheniramine	Chlortimeton, Allerest
clemastine fumarate	Tavist
dexbrompheniramine	Drixoral

Allergy Alert

If you ask your pharmacist for the generic version of your doctor's brand name suggestion, you may well get a different preparation. Check that the generic name is the same as the one your doctor recommended.

What are second generation antihistamines (prescription)?

The newer antihistamines are available by prescription only and are often referred to as "non-sedating." In general, this group of antihistamines is more expensive, has a slower onset of action, is longer acting, and induces less sleepiness. Even some of these can be slightly sedating (see Table II).

Allergy Alert

Two of the earlier second generation antihistamines, Seldane (terfenadine) and Hismanal (astemizole), were found to have unacceptable heart side effects and are no longer available on the market.

Table II: Second Generation Antihistamines

Generic Name	Brand Name	Usual Dosage
loratadine (non-sedating)	Claritin tablet/redi-tab 10mg, Claritin syrup 5mg/tsp	10mg once per day
fexofenadine (non-sedating)	Allegra capsule 60mg	60mg twice per day
cetirizine (slightly sedating)	Zyrtec tablet 5mg or 10mg, Zyrtec syrup 5mg/tsp	10mg once per day
azelastine (slightly sedating)	Astelin Nasal Spray	Two sprays in each nostril two times per day

Antihistamines perform best when taken regularly or before an allergic reaction begins. The second generation antihistamines may take up to an hour or more to become effective. They should be taken well before an expected allergic exposure, such as a visit to a friend who has a cat.

What are common side effects of antihistamines?

Since the first generation antihistamines can penetrate the brain tissue, they generally cause more side effects than the second generation drugs, which usually cannot enter the central nervous system. Drowsiness is the most noticeable side effect, but this is sometimes desirable. For example, it may be useful when nighttime symptoms prevent restful sleep. During the day, however, this effect can cause problems.

Allergy Alert

Be cautious about driving a car or operating a machine when using OTC antihistamines. Do not take any tranquilizers or drink alcohol along with these drugs. The combination may promote more drowsiness. Also, check with your doctor before taking an antihistamine if you have glaucoma or thyroid, heart, or prostate problems.

The first generation antihistamines may also cause troublesome anticholinergic effects such as heart palpitations, difficulty urinating, constipation, dry mouth, and nervousness. These side effects usually occur when the medication is taken at higher than recommended doses.

The second generation of antihistamines currently on the market has few, if any, significant side effects at the recommended doses.

Allergy Assist

Antihistamines may be used for nasal symptoms in patients with asthma. It was previously thought that these drugs would dry up the airways in the patient's bronchial tubes and aggravate the asthma. However, there is no good evidence supporting this notion. Additionally, as you will learn, improving nasal symptoms may benefit patients with asthma.

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

Generic Name	Brand Name
pseudoephedrine (oral: liquid, tablets)	Sudafed (Novafed)
phenylephrine (topical: drops, spray)	Neosynephrine
oxymetolazone (topical: drops, spray)	Afrin

When should I use topical decongestants?

The best use for topical decongestants, the nose drops and sprays, is for the quick, temporary relief of nasal stuffiness due to either allergic or non-allergic causes. They are helpful for relieving congestion in the Eustachian tubes, which equalize pressure between the inner ear and the nasopharynx. Decongestants are frequently used, therefore, before air flights to prevent ear symptoms during flight. In this regard, they may also be useful in treating ear infections. It is important, however, not to use these topical agents for longer than 3 to 5 days, since this may cause rebound congestion. Also, be careful to follow the daily use instructions - some decongestants need to be taken only twice a day while others may need to be used 3 to 4 times a day.

Allergy Fact

Nasal decongestants are effective in opening the entrances to the sinus cavities. This is particularly helpful in treating sinusitis and relieving sinus pressure.

The oral form of decongestants is the preferred choice for most cases of nasal congestion, particularly when you expect to use them for more than 3 to 5 days. They can also be taken for Eustachian tube blockage, infected ears, and sinusitis. Oral decongestants rarely cause rebound nasal congestion even if taken for long periods.

What are side effects of decongestants?

Topical sprays sometimes cause burning or dryness in the nose. The most well known side effect of topical decongestants is rebound nasal congestion. The longer you use the spray, the less effective it becomes and the more you find you need to use it in order to obtain the desired effect (virtually an addictive quality if used excessively). After prolonged use, the spray begins to cause more congestion than it relieves. The only way to break this cycle is to stop the medication. If the cycle is not broken, permanent changes can occur on the nasal membranes, which lead to a condition known as rhinitis medicamentosa. Rhinitis medicamentosa refers to an inflammation in the nose that is caused by the use of medications. Symptoms include severe stuffiness, burning, bleeding, and dryness of the nose.

Side effects from oral decongestants are more common and potentially more dangerous. They can stimulate the nervous system causing palpitations, insomnia, nervousness, and irritability. Some people may have trouble with urination and a decreased appetite. Although frequently mentioned, high blood pressure is not commonly caused or worsened by these drugs. If you have any concerns regarding the side effects of these drugs, discuss them with your doctor.

What about combination antihistamine/decongestant preparations?

Pharmacy shelves are packed with these preparations. They are useful for runny, itchy, and stuffy noses and are available OTC or by prescription. The liquid preparations are convenient for children as well as the elderly who may need a lesser dosage than is available in tablet forms. 12- and 24-hour preparations are available to make taking the medications more practical. Interestingly, the stimulant effect of the decongestant may counteract the drowsiness effect of the antihistamine and make the combination well tolerated.

Allergy Fact

Six of the top ten highest selling nonprescription medications (in 1990) were Dimetapp, Benadryl, Actifed, Drixoral, Comtrex, and Chlortrimeton. OTC antihistamine sales exceed $500 million per year and up to $2 billion per year when antihistamine-decongestant combinations are included.

Table IV: Common Antihistamine/Decongestant Preparations

Generation	Brand Name	R = Rapid Release S = Sustained Release	Antihistamine	Decongestant
First	Bromfed Tabs	R	Brompheniramine 4mg	Pseudoephedrine 60mg
	Deconamine Tabs	R	Chlorpheniramine 4mg	Pseudoephedrine 60mg
	Rondec Tabs	R	Carbinoxamine 4mg	Pseudoephedrine 60mg
	Ornade	S	Chlorpheniramine 12mg	Pseudoephedrine 120mg
	Tavist D	S	Clemastine 1.34mg	Pseudoephedrine 120mg
	Trinalin Repetabs	S	Azatadine 1mg	Pseudoephedrine 120mg
Second	Allegra D	S	Fexofenadine 60mg	Pseudoephedrine 120mg
	Claritin D 12-hour	S	Loratadine 5mg	Pseudoephedrine 120mg
	Claritin D 24-hour	S	Loratadine 10mg	Pseudoephedrine 240mg
	Semprex D	S	Acrivastine 8mg	Pseudoephedrine 60mg

Two broad categories of decongestants are available. Rapid release products need to be taken 3 to 4 times a day and provide a lower dose of both the antihistamine and decongestant. These medicines help people who are more troubled by side effects but they are less practical than the sustained release preparations, which need to be taken only once or twice per day.

Allergy Alert

When you switch OTC antihistamine/decongestant combinations, please read the label. Make sure the ingredients and the dosages are different from the ones you used to take. Otherwise, you may be buying the same medication with a different name, color, shape, and price.

Table V: Nasal Symptoms and Medicine

Nasal Symptom		Medicine
A	Sneezing	Antihistamine
	Runny Nose
	Itchy Nose/Throat
B	Stuffy Nose	Decongestant
C	Combination of Symptoms A + B	Antihistamine + Decongestant

Nasal Steroid Sprays

Steroids are naturally-occurring hormones that are produced by the adrenal glands. The corticosteroids have potent anti-inflammatory effects and are very effective in treating allergic inflammation in the nose. They are a "controller" type medication and work best when used on a regular "preventative" basis. With seasonal allergies, daily use of these sprays should begin 1 to 2 weeks before the allergy season and continue throughout the season. In year round or perennial allergic rhinitis, particularly if unresponsive to treatments, daily use of intranasal steroids has been found very effective in controlling symptoms, particularly nasal congestion. The addition of antihistamines to this nasal spray will likely give even better results.

Nasal steroids may also help improve the sense of smell, which is frequently diminished in allergic rhinitis. The medication may work by reducing swelling high up in the nose, where the area for smell is located. Decreasing the swelling allows more air (containing the odors) to reach the nerves that are responsible for the sense of smell.

Allergy Assist

Bag-like collections of fluid in the nasal membranes, called nasal polyps, are not uncommonly found in allergic rhinitis. Nasal steroids are helpful in shrinking nasal polyps and in preventing them from recurring.

Nasal steroids are available in two forms, aerosol and a spray pump (aqueous). The aerosol form resembles an asthma spray that delivers a predetermined dose of "dry" medication when activated. The more commonly used pump delivers a "water-based" spray, which may provide some moisturizing and soothing effect as well as an anti- inflammatory action. Patients who feel that the drip in their nose and throat increases when using the spray form may prefer the aerosol. In contrast, the spray is favored if the aerosol causes irritation or excessive drying of the nasal membranes.

Allergy Fact

In 1960, the first nasal steroid spray, Decadron Turbinaire, was introduced in the United States. Although very effective, too much of the drug was absorbed into the bloodstream, which resulted in side effects and limited its use. A different medication, Beclomethasone, was initially marketed in the 1970s and has been well tolerated.

Table VI: Common Intranasal Steroids (See Appendix.)

Generic Name	Brand Name
beclomethasone	Beconase, Vancenase (pump, aerosol)
flunisolide	Nasarel, Nasalide (pump)
triamcinolone	Nasacort, Nasacort AQ (pump, aerosol)
budesonide	Rhinocort (aerosol)
fluticasone	Flonase (pump)
mometasone	Nasonex (pump)

The latter of these intranasal steroids - Rhinocort, Flonase, and Nasonex - are faster acting and more potent than the other nasal steroids, with no difference in side effects.

The safety record of nasal steroids at the recommended dosages is excellent. Several studies conducted in the U.S., Canada, and Europe have documented the lack of significant systemic (general body) side effects. The common side effects occur locally in the nose, such as burning, stinging, dryness, and sneezing, and are usually reported with the use of dry aerosol sprays. Less common effects include headache and mild nasal bleeding. The latter can be avoided by good spray technique. Shallow nasal ulcers are rare and can also be avoided by the use of good technique.

Corticosteroids are occasionally prescribed orally for a few days in cases of severe allergic rhinitis with almost total obstruction of the nasal passages. In these cases, antihistamines, decongestants, and certainly nasal sprays are not likely to help. After the nasal passages have opened, however, the nasal sprays can be used to prevent further swelling.

Other Nasal Sprays That Might Help

Ipratropium Bromide Spray (Atrovent)

Ipratropium bromide blocks the effects of acetylcholine, which is a chemical that, among other actions, signals the mucous glands in the nose to produce mucous. Allergic reactions can trigger excessive acetylcholine activity on the mucous glands. Ipratropium bromide occupies the same receptor on the glands as does acetylcholine and in this way reduces mucous secretion. You see, the ipratropium bromide that replaces acetylcholine on the receptor does not stimulate mucus secretion.

Ipratropium Bromide is available as a spray pump and comes in two strengths (0.03% and 0.06%). It is only effective for runny noses and can literally "turn off the faucet." The drug does not help itchy or stuffy noses and does not usually take the place of an intranasal steroid, but rather is used along with it. Typically, two sprays 3 to 4 times per day in each nostril are required to control symptoms. Once improvement is seen, the dose can often be lowered to one spray 3 to 4 times per day or two sprays 2 times per day.

Side effects of ipratropium bromide are infrequent but include dry nose, nasal irritation, and nose bleeding. If accidentally sprayed into the eyes, the drug may cause temporary blurred vision.

Allergy Assist

Ipratropium bromide nasal spray can dry up mucous, regardless of the cause. The spray may be effective in non- allergic rhinitis and even the common cold (usually at the higher 0.06% dose).

Cromolyn Sodium Nasal Spray (Nasalcrom)

Cromolyn works to reduce nasal inflammation without the use of steroids. It acts on mast cells to stabilize them, thereby preventing the release of histamine and other mediators. Since cromolyn is strictly a "controller" medication, it must be taken before allergic exposure, usually at least 2 weeks prior, due to its slow onset of effectiveness. The drug tends to be more effective in younger people with higher levels of IgE. It is given at doses of one to two sprays in each nostril 4 times per day. Cromolyn appears to be helpful in reducing runny nose, sneezing, and congestion in milder cases, but may not be effective at all in more severe cases. The medicine became available OTC in 1997. It is a particularly well tolerated medication with minimal side effects (usually sneezing, nasal irritation, or stinging. Rare cases of nasal bleeding or residual bad taste are reported.) There are no systemic, or body-wide, side effects.

Allergy Assist

Cromolyn nasal spray is safe for pregnancy, lactation, and children under the age of 6 years old.

Tips for Proper Use of Nasal Sprays

Using a good technique in applying nasal sprays will help you achieve the maximum benefits from the medications and avoid certain side effects, such as nasal bleeding. The following are guidelines for proper spray technique:

• Clear your nasal passages with gentle nose blowing or a nasal decongestant for a few days when starting nasal steroids.
• Shake the container.
• Place one finger over one nostril to close it off.
• Place the tip of the spray into the open nostril pointing away from the nasal septum (midline) and direct the spray straight back, not up into the tip of your nose.
• Activate the spray, sniffing in gently and deeply as you do so.
• Exhale through the mouth.
• Repeat these steps for the other nostril.
• Never "double" spray: always spray one nostril at a time and alternate nostrils each time.

Nasal Allergies At A Glance

• Nasal allergy is an inflammatory reaction to house dust mites, mold, animal hair, and pollens.
• Take antihistamines for sneezing, runny nose, itchy nose and throat.
• Take decongestants for nasal congestion only.
• Anticholinergic medicine such as Ipratropium Bromide may help with intractable runny noses.
• Nasal steroids are safe and effective on a runny, itchy, and particularly stuffy nose.
• Combination of antihistamine, decongestant, and steroid inhalers are a good choice for moderate or severe hay fever.
• Topical nasal decongestant should be limited to use for 3 to 5 days maximum.

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