Hay-fever sufferers now have more to worry about than just the itchy eyes, runny nose, sneezing, and congestion that afflict them each spring. Scientists have discovered that hay fever, or allergic rhinitis, is actually the first phase of an allergic process that, in up to one-half of people who have it, may contribute to a far more serious disease—asthma.

But research suggests that allergy shots, long relegated to a minority of rhinitis patients by most doctors, may help prevent that harmful progression. Moreover, the injections can reduce the frequency and severity of asthma attacks, with or without rhinitis, in the 60 to 70 percent of asthma sufferers whose disease stems from allergic causes.

It’s still generally best to try simpler, better-established measures first: avoiding the substances that trigger the reactions and taking allergy medication. That can help relieve not only rhinitis but also any accompanying asthma or sinusitis (inflammation of the passages surrounding the nose). Unfortunately, the ever-expanding array of nonprescription options, including some that recently went over-the-counter and others that can worsen your symptoms, makes choosing the right drug difficult. Letting your doctor choose doesn’t ensure the optimal medication, either. Studies show that the most effective prescription drugs for rhinitis and asthma—steroids sprayed into the nose or inhaled into the lungs—are not prescribed often enough.

Here’s a guide to the latest expert advice on treating rhinitis, asthma, and other interconnected allergies.

Researchers now regard allergic rhinitis as well as the allergic forms of asthma and sinusitis as different stages in a single disease of the entire airway. The problem starts with an impaired immune system that treats essentially harmless substances, such as pollen and dust mites, as if they were deadly intruders. When allergic individuals breathe such allergens into their nostrils, the body mounts a potent counterattack that causes a runny nose, teary eyes, and other discomfort.

But it now appears that the allergic response also unleashes inflammation throughout the lungs and sinuses, even when the allergen never reaches them. That can constrict the bronchial tubes and increase mucus production, causing the wheezing and coughing of asthma; it can also block the sinuses, provoking the pain and congestion of sinusitis. Further, the inflammation predisposes the sinuses and lungs to infection, which can trigger asthma attacks and worsen sinusitis. And the allergic reaction in the nostrils may make the entire airway more sensitive to subsequent allergen exposure.
Attempting to avoid the offending substances is essential, regardless of other treatments. If necessary, keep a diary listing when and where your symptoms occur and, if possible, what specifically provokes them. To limit exposure to common indoor allergens—such as dust mites, pet dander, and cockroach droppings—wash your sheets in hot water, don’t cover your floors with thick carpets, use a dehumidifier or air conditioner to reduce humidity, and, as a last resort, consider using an air cleaner.

It’s harder to avoid outdoor allergens, such as pollen, but you can minimize exposure by keeping windows shut and staying indoors as much as possible when allergen levels are highest, typically between 5 a.m. and 10 a.m.

In addition, most rhinitis sufferers will need at least antihistamine medication. The best antihistamine is often the generic form of loratadine (Claritin). It’s less sedating than other nonprescription antihistamines, such as chlorpheniramine (Aller-Chlor) and diphenhydramine (AllerMax, Benadryl Allergy), and it costs less than comparably safe and effective prescription antihistamines, such as cetirizine (Zyrtec) and fexofenadine (Allegra). But a May 2004 study found that doctors recommend those costlier drugs more often, possibly because of intense advertising for the prescription medicines.

For more-severe rhinitis, steroid nasal sprays, such as budesonide (Rhinocort Aqua) and fluticasone (Flonase), provide better relief by quelling the underlying inflammation. They can also help control sinusitis and mild, intermittent asthma.

Inhaled versions of those steroids, such as Pulmicort and Flovent, are necessary for anyone with persistent asthma, because they help prevent attacks and keep the disease from worsening. In contrast, the other main asthma drugs—bronchodilators such as albuterol (Proventil, Ventolin) and metaproterenol (Alupent)—merely treat the attacks.

Because the doses are low, the steroid mists are much less likely to cause the side effects associated with steroid pills. And they’re not particularly costly: about $35 to $70 per month for the nasal sprays, $45 to $60 for the inhaled versions. But because physicians don’t prescribe them often enough, you may need to ask your doctor either for the spray if the antihistamines don’t control your rhinitis or for the inhaled drug if you have frequent asthma attacks.

Immunotherapy, or injections of progressively larger doses of one or more offending allergens until immunity develops, can often help when lifestyle measures and drugs alone aren’t sufficient. Moreover, people who have rhinitis plus an increased risk of asthma (see What you can do ) should consider the shots even when other measures provide adequate relief.

In one of the largest and best clinical trials of such preventive immunotherapy, the shots cut rhinitis patients’ risk of asthma nearly in half, from 44 percent to 24 percent over three years. While that and two smaller studies with similar findings involved children, the shots theoretically should help prevent asthma in adults, too.

Other research indicates that the injections help control not only rhinitis but also asthma and sinusitis in allergic children or adults who already have those conditions. The shots appear to help even some people whose main or sole problem is asthma, not rhinitis. Treatment guidelines from the Joint Council of Allergies, Asthma, and Immunology endorse immunotherapy for allergic asthma.

The shots may cost less than drug therapy and are usually covered by insurance. But immunotherapy has certain downsides that make it inappropriate for some people. First, it requires weekly or biweekly injections for about four months, then monthly booster shots, usually for three to five years. After each injection, you must stay at the doctor’s office for about a half-hour in case of anaphylactic shock, the therapy’s main risk. People especially vulnerable to such shock—including those with kidney failure or heart disease, or uncontrolled asthma, angina, or hypertension—should avoid the shots.

Individuals who can’t undergo immunotherapy or don’t get adequate relief from the shots plus standard medication could consider injections of omalizumab (Xolair). That drug, introduced in 2003, appears to help relieve both rhinitis and asthma by preventing the misplaced immune-system counterattack. But its high cost—$1,000 or more per month—and lack of long-term safety data make it a last-resort option.

Start by identifying your allergy triggers, then try to avoid them, even if you also take drugs or get allergy shots.

People with mild rhinitis can add antihistamines, especially loratadine, to ease itching, sneezing, and a runny nose; those with more-severe symptoms or frequent congestion usually need nasal steroid sprays. Inhaled versions of those sprays are the best treatment for asthma.

The shots should be considered for:

• Rhinitis sufferers at increased risk of asthma, including children and anyone with a family history of that disease.

• Individuals with rhinitis plus sinusitis, asthma, or both.

• Anyone with rhinitis, sinusitis, or asthma whose drugs fail to provide relief or cause unacceptable side effects, or who want to reduce or possibly eliminate reliance on those medications.

• People who react severely to bee, hornet, or wasp stings. (But the shots rarely work against food allergies.)

Note that the injections can take four to six months, on average, to start relieving symptoms, and that many people must keep taking at least some medication. It’s best to start the shots before seasonal allergies kick in or after other drugs have controlled symptoms.

If you suspect you are suffering from hay fever or other allergies, make an appointment with your doctor soon. Prompt, proper treatment of allergies can control symptoms and restore your quality of life. With so many drug and non-drug treatment options available, having up-to-date, unbiased information is critical to your health.