It’s not a cold, so your runny nose must be due to an allergy, right? Wrong! Allergic causes of rhinitis, the medical term for runny nose, account for only 10-15% of cases. The majority of nasal symptoms result from non-allergic, non-infections causes.
In addition to providing us with our sense of smell, the nose conditions and cleans the air we inhale. In its passage through the nose, air is warmed, humidified, and cleaned of foreign particles and microorganisms. Thus, when the air we inhale reaches the throat, it is at body temperature and at 100% humidity. To accomplish this conditioning feat, the lining of the nose produces approximately two quarts of mucus per day, which gives up heat and water to the inhaled air. The mucus also traps foreign matter such as bacteria and viruses and transports them to the throat, where the mucus and everything trapped within it is continuously swallowed. The cells producing the nasal mucus, and the small blood vessels in the lining of the nose which control the amount of mucous membrane congestion, are under the control of the autonomic nervous system, which responds automatically to changes in conditions presented to the nose. A typical example of this is the sneeze, a reflex reaction to a noxious stimulus.
In a group of nasal disorders referred to as “vasomotor rhinitis”, the common denominator is an abnormal response of the autonomic nervous system controlling nasal mucus production and mucous membrane congestion. The end result is increased nasal secretions, resulting in so-called “postnasal drip.” Mucous membrane swelling causes congestion that becomes bothersome because it causes an increase in the work of breathing.
Vasomotor rhinitis may be triggered by medications used for control of other medical conditions. For example, drugs that are useful in controlling high blood pressure, such as prazosin, methyldopa, propranolol and naldolol, may cause these nasal symptoms. Estrogens, in oral contraceptives, and which increase during pregnancy or in the premenstrual period, can cause vasomotor rhinitis as well.
In vasomotor rhinitis the nose tends to be “hyperreactive,” that is, overreacting to normal changes in temperature and humidity and to the presence of irritants such as tobacco smoke or strong perfume. Emotional state and stress may also adversely affect the autonomic nervous system, and thus produce changes in nasal function.
Treatment of vasomotor rhinitis is often frustrating. Successful treatment depends upon accurate diagnosis and elimination or avoidance of factors that trigger symptoms. If anti-hypertensive medications appear to be involved, switching to a different type of drug is often helpful. Hormonal aberrations such as hypothyroidism and pregnancy should be ruled out through appropriate examination and testing.
Unhappily, response to medication is frequently unsatisfactory. Oral decongestants may be of benefit to some, and some antihistamines may give temporary relief because of their effect on drying up nasal mucus. Topical nasal steroids, such as beclomethasone and flunisolide, may also be of benefit. Ipratropium bromide, an agent useful in the treatment of asthma, has been shown to be effective in controlling the rhinorrhea, but not the congestion of vasomotor rhinitis.
Surgical procedures to correct nasal septal deformities or reduce the size of the nasal turbinates are sometimes used to control severe vasomotor rhinitis that does not respond to medical treatment. Surgical intervention is a treatment of last resort, not without its own risks and adverse side effects.
If you have questions about Vasomotor Rhinitis, feel free to contact our offices. One of our staff would be happy to answer your questions about Vasomotor Rhinitis and discuss different treatment options offered at Allergy & Asthma Clinics of Ohio.