If spring brings a stuffy nose, scratchy eyes and an extra sneeze tacked on to your usual "achoo!" — You probably have hay fever (allergic rhinitis). Hay fever is the common name for an allergic response to specific substances in your environment. Hay fever is one of the most common allergic conditions, affecting about 40 million people in the United States.

If you have seasonal hay fever, tree pollen, grasses or weeds may trigger your symptoms. If you're sensitive to indoor allergens such as dust mites, cockroaches, mold or pet dander, you may have year-round symptoms.

Over-the-counter medications may be enough to manage your mild hay fever symptoms. But if your signs and symptoms are more severe — or if hay fever is a year-round nuisance — see an allergy specialist for evaluation and treatment. Without proper treatment, hay fever can impair your quality of life, cause sleeplessness, fatigue and irritability that affect your performance at work or school, and increase your risk of developing more serious allergic conditions such as asthma or eczema.

Signs and symptoms- of hay fever can range from mild to severe. If your condition is mild, you may have brief, infrequent episodes of a runny nose and itchy, watery eyes. At the other extreme, you may experience persistent, severe symptoms that last more than four days a week or longer than four weeks at a time. Chronic congestion may cause facial pressure and pain, alter your sense of taste and smell, and affect your appearance. The skin beneath your eyes may swell and turn blue-ish as you develop what are sometimes called "allergic shiners."

Hay fever signs and symptoms usually develop immediately after you're exposed to specific allergy-causing substances (allergens). Common allergens include pollen, dust mites, cockroaches, mold and pet dander. Sometimes, exposure to irritants such as perfume and tobacco smoke may trigger or worsen symptoms.

It may be difficult to distinguish hay fever from a cold. Here's how to tell the difference:

Heredity plays a key role in determining who gets allergies, including hay fever. You may be more likely to develop hay fever if allergies or asthma runs in your family.

Although hay fever can begin at any age, you're most likely to develop it during childhood or early adulthood. As you get older, your symptoms may worsen or improve. The severity of hay fever tends to diminish slowly, often over decades.

If you have hay fever, you may react to one or more common inhaled allergens. No matter what you're allergic to, the underlying cause of your misery is the same. During a process called sensitization, your immune system mistakenly identifies the allergen as an invader and produces an antibody against it called immunoglobulin E, or IgE.

The next time you're exposed to the allergen, your immune system launches an allergic reaction. The IgE antibodies trigger the release of an inflammatory chemical called histamine, which swells the mucous membranes in your nose, sinuses and eyes, causing a runny nose, watery eyes and sneezing.

Self-care -It's not possible to completely avoid allergens, but you can reduce your signs and symptoms by minimizing your exposure to them. To reduce exposure to pollen or molds:

Resource: Mayo Clinic