8 Reasons You Have a Runny Nose

Does every season seem to be the season for a runny nose? That is because there are 8 common reasons you can have rhinorrhea (runny nose), and not all of them are limited to winter. In fact, there are many reasons to have a runny nose all year long. Despite this bad news, there are things you can do to help prevent a runny nose, or at least minimize the pesky symptoms that go along with it.

The Common Cold

Sick woman laying on sofa holding remote control. — Tom Merton / Getty Images

Also known as: upper respiratory infection (URI)

The common cold causes a runny nose by increasing the permeability of blood vessels in the nose. This allows for leakage of fluid (serum) into the nasal passages. Rhinorrhea commonly occurs with the first 2 to 3 days after becoming infected with a common cold virus. Unfortunately, every year millions of people are plagued with the common cold.

The common cold is commonly caused by viral infections including:

rhinovirus - most common
coronavirus
respiratory syncytial virus (RSV)
metapneumovirus

In the United States alone, 21 million school days and 20 million workdays are missed each year due to the common cold. On average, most children are sick between 5 to 7 times each year due to the common cold; however, 10 out of 100 kids may be sick as much as 12 times in a year. Incidence decreases as you enter adulthood, decreasing to approximately 2 to 3 times each year.

Prevention of the common cold is difficult. The virus can be acquired by direct contact with someone else that has the illness, or can be encountered by inhaling particles in the air from someone infected in your area. Vitamins and herbal supplements like vitamin C, zinc, vitamin E, echinacea, and ginseng offer no benefit in preventing the common cold. While exercise has not been shown to prevent the common cold, it is closely linked to improved health in general.

Common treatments to help reduce a runny nose in the case of the common cold include using intranasal ipratropium (Atrovent) or first-generation antihistamines (see below):

brompheniramine (found in Dimetapp Cold & Allergy)
chlorpheniramine (found in Chlor-Trimeton)
dimenhydrinate (found in Dramamine)
diphenhydramine (found in Benadryl Allergy)

If your runny nose persists more than 10 days, you may want to see a physician, as you may have a bacterial infection that can be treated with antibiotics.

Allergies

Woman blowing her nose at outdoor cafe — LeoPatrizi/iStock

Also known as: hay fever & allergic rhinitis

Allergic rhinitis is a seasonal reason for having a runny nose. You may commonly experience a runny nose related to allergies during the spring or the fall. The runny nose is caused because of your body's inflammatory response due to pollen that is in the air from: flowering plants, trees, weeds, and grasses. Nasal secretions from allergies are most commonly clear, however, they may also appear purulent.

First line treatment of mild to moderate symptoms related to allergies is an oral antihistamine or nasal antihistamine spray. Glucocorticoid nasal sprays are also effective.

While antihistamines will help with the runny nose, antihistamines are ineffective in treating allergy-related nasal congestion.

Cold Air

Woman blowing nose outside. — Axel Bueckert / EyeEm / Getty Images

Have you gone outside to enjoy the fresh snow only to have a runny nose ruin the moment? If outside long enough, you might even develop chapped lips from constantly wiping your nasal secretions away from your upper lip. You are not alone. This is a common phenomenon.

Cold, dry air is known to dry out the nasal membranes, which changes the fluid balance in your nasal passages. The change causes a cascade of your inflammatory response and nasal nervous system reflexes which will cause your nose to run.

Eating Spicy Food

Hot peppers in a mason jar. — by JBfotoblog/Getty Images

Also known as: gustatory rhinitis

A runny nose caused by eating food is not well understood. The reaction is not suggested to be an immune response but is more likely related to stimulation of the nervous system (trigeminal nerve) and may be associated with a parasympathetic response, a response that is helpful in resting and digesting.

You are also more likely to suffer from this if you also have allergic rhinitis or a history of smoking.

While hot and spicy foods are thought to be the main contributing foods, any food can cause you to experience a runny nose if you suffer from gustatory rhinitis. Foods consisting of grains (breads, crackers, etc...) are less likely to cause a runny nose, while spicy foods (hot chili peppers, red cayenne, Tabasco sauce, etc...) are more common.

Symptom reduction of gustatory rhinitis is mainly avoidance of spicy foods. However intranasal atropine has also been helpful when avoidance of spicy foods is undesirable. Surgery, while can be helpful, is not utilized due to other side-effects of the procedure.

Hormones

Pregnant woman holding stomach. — Hero Images / Getty Images

Also known as: hormonal rhinitis

Hormones can cause a direct effect on the membranes in your nasal passages, causing your mucous glands to become more reactive. Levels of thyroid, growth, and female sex hormones all have shown to play roles in hormonal rhinitis.

A runny nose and congestion is also a prevalent symptom during pregnancy and is experienced by 39% of pregnant women. During pregnancy, changes to blood vessel throughout a woman's body can result in the pooling of blood in the nasal blood vessels. The increased levels of progesterone can also cause your blood vessels to not relax as normal and result in this as well. Symptoms related to rhinitis during pregnancy seems to mirror the levels of estrogen.

There is little information available on the treatment of hormonal rhinitis. Hormone replacement therapy does not seem to help in the resolution of symptoms.

If you are pregnant, you can try nasal saline spray or exercise to potentially help alleviate symptoms. These medications may also be considered for pregnant or breastfeeding women, but do not take unless you have cleared it with your obstetrician:

Pseudoephedrine
Claritin
Zyrtec
Atrovent

Many other possible treatments may be considered harmful to your baby, so always involve your doctor before starting a new medication.

Medications

Also known as: medication-induced rhinitis

Some medications are known to have the side-effect of a runny nose. Each medication class will have a different reason for causing rhinitis; however, all of them are related to changes in the body caused by the medication. Some of the medications targeted to treat the following conditions may cause you to experience a runny nose:

high blood pressure
enlarged prostate
birth control
pain
erectile dysfunction
depression
cardiovascular disease

Side-effects of medications vary widely and you may not always experience rhinitis if you are taking any medications related to the list above.

Exercise

Two women running. — Holde Schneider / Getty Images

Also known as: vasomotor rhinitis

Aerobic exercise (running, aerobics, intercourse, etc...) may be the cause of your runny nose. However, if you experience a runny nose while being active outdoors, the cause may be more realistically related to allergies, cold weather, or another irritant. If you experience a runny nose frequently while being active, you can ask your physician if Atrovent, a nasal anticholinergic, would be a good choice for you.

Crying

Crying naturally causes you to have a runny nose because of the way your tears drain from your eyes (through the lacrimal puncta). You are constantly generating tears to keep your eyes from drying out. These tears do not run down your cheeks like they do when you cry. Crying generates more tears than can be drained, so they run over your cheek.

While crying, more tears flow through the lacrimal puncta into the nasolacrimal duct. This tube drains directly into your nose, so your runny nose is actually your tears that have drained into your nose.