Can Allergies Cause Swollen Lymph Nodes?

You’re probably familiar with the annoying symptoms of an environmental allergy episode, including sneezing, watery eyes, itching, and coughing. Can allergies cause swollen lymph nodes, too? When this symptom develops, it’s important to understand why it’s happening. While you might notice it along with other common allergy symptoms, the underlying cause is likely different.

Typically, an environmental allergy is not the true cause of swollen glands. However, it can be the first domino in a series of events that leads to this type of physiological response. Over time, persistent irritation and sinus drainage can lead to inflammation in the sinus cavity, ultimately causing an infection. When this occurs, the lymph nodes can swell in response.

Other types of allergies may trigger swelling and are more serious. These may include allergies to certain:

Foods
Drugs
Insect bites or stings

If any of these events cause noticeable or serious swelling anywhere in the body, not just in the lymph nodes, seek medical care promptly. Swelling as an allergic response could be the start of anaphylaxis, a life-threatening condition that requires immediate treatment.

Understanding the Lymphatic System

What exactly is happening when your lymph nodes swell? These glands are a part of your body’s lymphatic system, which is responsible for numerous important tasks. It helps regulate fluid levels throughout the body and removes wastes after the cells filter them from the bloodstream. It also helps protect you from disease and illness by producing and releasing certain white blood cells to attack foreign substances, such as bacteria.

Lymph Nodes

The glands of the lymphatic system are located throughout the body and act as small filters. As lymph fluid travels through the body and carries out waste and foreign bodies, it passes through the lymph nodes. When unwanted bacteria grow or reproduce in the body, the lymph nodes may produce and accumulate a high number of white blood cells to fight them off, resulting in inflammation.

You can find dozens of lymph nodes from head to toe. When they are grouped closely together in large clusters, it’s more noticeable when the tissues become inflamed. The glands in the neck tend to be the most obvious location when swelling occurs, but there are also groupings in the armpits, groin, pelvis, and chest. Typically, the lymph nodes closest to the site of the infection will swell the most.

Common Causes of Swollen Lymph Nodes

Can allergies cause swollen lymph nodes? It’s unlikely when pollen or pet dander are the triggers, but there are several other conditions that can lead to this symptom.

Illnesses and Infections

If your lymph nodes swell when you have a cough or runny nose, you’re more likely dealing with a cold than an allergy issue. When a virus or infection enters the body, the immune response activates certain white blood cells, leading to inflammation throughout the lymphatic system. Swollen lymph nodes in the neck are sometimes associated with respiratory conditions or illnesses of the ear, nose, and throat, such as:

Strep throat
Sinus infections
Bronchitis
Flu
Ear infections
Tuberculosis

Lymph nodes in the abdomen or along the groin may swell in response to an STI, such as gonorrhea or syphilis.

Autoimmune Conditions

When the body mistakes a natural organism for a foreign one, it can initiate an immune response that attacks these healthy tissues. This is the definition of an autoimmune disease, which can sometimes trigger swelling in the lymph nodes. Rheumatoid arthritis and lupus flare-ups are some of the most common types that lead to inflammation throughout the body and within the lymphatic system.

Cancer

Although less common, swollen lymph nodes can be a result of certain types of cancer. Most often, the culprit is lymphoma, either Hodgkin’s or non-Hodgkin’s, or leukemia. Unexplained swelling that lasts for more than a few weeks and tends to worsen or grow over time requires evaluation by a doctor to rule out cancer. You should also seek medical care if the glands grow to more than half an inch in size.

Stress

Elevated stress levels are a normal part of life, but when the increase becomes chronic, it can seriously harm your health. All that cortisol coursing through your system can leave you more prone to inflammation and can weaken your immune system. While the stress response itself does not lead directly to swollen lymph nodes, it can leave you very vulnerable to the illnesses and conditions that do.

Medications

All medicines, whether prescription or over-the-counter, come with the risk of side effects. Most are relatively minor. However, certain drugs can affect the lymphatic system and lead to swelling of the lymph nodes, such as antimalarial or antiseizure meds. Talk with your doctor about what to expect and when to report new symptoms and potential drug reactions.

Dental Issues

Studies have shown that dental health, especially concerning your gums, can have a direct impact on your overall risk for certain diseases and medical conditions. People with gum disease are more likely to develop or experience:

Diabetes
Cardiovascular Issues
Stroke
Pregnancy complications
Certain cancers

Periodontal issues often arise from a lack of proper dental hygiene. Food particles and bacteria become trapped along and beneath the gum line without adequate brushing and flossing on a routine basis. This constant presence of harmful bacteria can trigger an immune response that leads to swollen lymph nodes. This is especially true if it leads to an infection or abscessed tooth.