Vasomotor rhinitis
Synonyms: Idiopathic rhinitis, nonallergic rhinopathy
Vasomotor rhinitis is a form of rhinitis that is not related to allergic reactions, but which is characterized by many of the same symptoms, such as a chronic running nose with intermittent sneezing, rhinorrhea and blood-vessel congestion of the nasal mucus membranes. Vasomotor rhinitis is to be distinguished from sinus infection or other forms of allergy.

# Pathophysiology
Nonallergic rhinitis- It encompasses a heterogeneous group of nasal conditions with diverse pathophysiology. Unlike allergic rhinitis, nonallergic rhinitis is characterized by periodic, seasonal, persistent or perennial symptoms of rhinitis  not resulting from IgE-dependent events. Imbalance in the maintenance of homeostasis between vasoconstriction and vasodilation of nasal vasculature and the secretion of nasal glands by sympathetic and parasympathetic components of the autonomic nervous system contribute to glandular hypersecretion and increased nasal congestion. Neuropeptides  secreted by unmyelinated nociceptive C fibers (tachykinins, calcitonin gene-related peptide, neurokinin A, gastrin-releasing peptide) and parasympathetic nerve endings (vasoactive intestinal peptide), have recently been established to be present in the nasal mucosa. Rhinitis can occur following exposure to nonallergic triggers, via activation of Transient Receptor Potential cation channels(TRPV1, TRPA1) on nasal mucosal nerve fibers, which result in the release of neuropetides such as Calcitonin Gene-Related Peptide (CGRP)and substance P from sensory nerve endings. These neuropeptides facilitate vasodilation and plasma extravasation, resulting in edema and glandular hypersecretion. It is important to note that the evidence for substance P involvement was extrapolated following the beneficial effect of treatment with capsaicin(known to deplete substance P from sensory nerve endings) in affected patients. These pathophysiologic mechanisms have not been extensively investigated. Subtypes of nonallergic rhinitis include:
- Vasomotor/idiopathic rhinitis- This is also sometimes referred to as nonallergic rhinopathy because there is a lack of nasal mucosal inflammation. The pathogenesis is unclear although neurosensory abnormalities have been suggested. The nasal mucosa of patients with vasomotor rhinitis is indistinguishable from those of normal subjects. Vasomotor rhinitis is a chronic nasal condition usually without eosinophia. It has been found to be associated with vasospastic disorders such as primary acrocyanosis. Triggers of vasomotor rhinitis include:
- Climatic changes(e.g humidity, temperature, barometric pressure)
- Irritants like strong smells (such as perfumes, cooking smells, flowers, and chemical odors), environmental tobacco smoke, pollutants and chemicals
- Exercise
- Trauma

# Causes
Vasomotor rhinitis is also known as non-allergenic rhinitis, because it often has the same symptoms as allergies, but has different causes.  Whereas allergenic rhinitis conditions (such as hayfever) are the result of the immune system overreacting to environmental irritants (pollen, etc), vasomotor rhinitis is believed to be caused by oversensitive or excessive blood vessels in the nasal membrane.  These blood vessels (which are controlled in turn by the autonomic nervous system) contract or dilate in order to regulate mucus flow and congestion.  But in the vasomotor rhinitis sufferer, oversensitive or excessive blood vessels causes an overreaction to such stimuli as changes in weather, temperature, or barometric pressure, chemical irritants such as smoke, ozone, pollution, perfumes, and aerosol sprays, psychological stress and emotional shocks, certain types of medications, and even spicy food. Thus, while a normal person's nose may run on a very cold day, a vasomotor rhinitis sufferer's nose may start running (or go completely dry) simply by walking into a slightly colder (or slightly warmer) room. While a normal person may tolerate a certain degree of cigarette smoke, the vasomotor rhinitis sufferer may experience significant discomfort from the same level of smoke.      
The pathology of vasomotor rhinitis is in fact not very well-understood and more research is needed.
Many patients can be subject to vasomotor rhinitis and allergic rhinitis simultaneously.

# Symptoms
Recurring nasal inflammation, swelling of the nasal membrane or profuse watery nasal discharge might signal vasomotor rhinitis.  Swelling of the nasal tissues can cause headaches.  Some people start sneezing when walking from a cold air-conditioned room into warmer air.

# Treatment
Vasomotor rhinitis cannot be cured completely but can be brought under a measure of control.  Avoidance of the irritants is a common sense method of controlling vasomotor rhinitis (though many irritants, such as weather changes, cannot of course be controlled). Prophylaxis therapy is also recommended as it will help protect the patient before being exposed to the irritant.
There are a number of medications that may be effective in the treatment of vasomotor rhinitis. In general, the available treatments are similar to those used in allergic rhinitis.
Ipratropium bromide is available in nasal spray formulation. It may be of benefit, particularly in the presence of marked rhinorrhoea.
Nasal corticosteroid sprays may be prescribed, and often work well when used regularly.  These control inflammation of the nasal tissues.
Oral decongestants, such as pseudoephedrine-based pills, may provide benefit, but are associated with side-effects such as nervousness and jitteriness, insomnia, hypertension, and so on.  (Pseudoephedrine is a sympathomimetic drug, which means that it simulates the effect of fight-or-flight chemicals, such as adrenaline, in the body.)  A trial and error reduction of dosage may alleviate the side-effects while maintaining the effectiveness.
Decongestant nasal sprays (as opposed to oral decongestants) are not recommended. These may provide short term relief, but excessive use may result in "rebounding" -- the nasal blood vessels get even more hypersensitive. Overuse or addiction to decongestant nasal sprays is actually a cause of vasomotor rhinitis.
Antihistamines are designed for use in allergic rhinitis and, while considered safe, are rarely effective.  Interestingly, azelastine, the only topical antihistamine spray currently available in the United States, has shown some benefit in non-allergic or vasomotor rhinitis.
Many patients find irrigation with nasal saline spray alleviates symptoms. Nasal saline spray dilutes irritants and mitigates their effects.  (Stir one teaspoon of non-iodised salt into 500 millilitres of boiled or distilled water, and pour into nasal spray dispensers when cool).
If saline spray does not provide relief, rinsing can be more effective. Rinsing actually involves flooding the nasal passages, and often some of the sinuses, with a solution. Rinsing is particularly effective for those with severe non-allergenic rhinitis which can produce large amounts of thick mucous that is difficult to expel.
For some patients, rinsing may be the only effective method for clearing the nasal passages, and can benefit the sinuses as well. Rinsing can quickly become the preferred treatment, as the effects can be dramatic, and probably will become a lifetime daily ritual for those with severe disease.  You cannot rinse too often, and symptoms each day dictate the frequency of rinsing.
Rinsing can be combined with daily or occasional use of pseudoephedrine, and/or corticosteroid nasal sprays when symptoms dictate.
Unlike other forms of treatment, rinsing will not produce any side effects such as dry throat or mouth, rebound effect, nervousness, or heart palpitations. The ideal solution is pH balanced. It contains sodium chloride (table salt), sodium bicarbonate (baking soda), and water. Measuring the salts is not really practical for most patients, due to the small quantities needed, and the likely need to rinse many times each day, unless there is no other choice.  Therefore, various commercial solutions are available which also include a special squeeze bottle for introducing the liquid through one nostril at a time while holding the other closed. Typically 8 ounces of water is used for each rinse.
An isotonic (balanced) solution is normally used.  Sometimes a hypertonic (higher salt content) solution may be employed; hypertonic solutions are thought to be better at reducing inflammation and drawing out mucus, though studies on the topic have not necessarily borne this out.
Rinsing may be useful to relieve any hearing disturbance due to the clogging up of sinuses by the mucus, which creates a different pressure behind the inner ear, and by the clogging of mucous in the back of the throat at the opening to the eustachian tube which leads to the middle ear, which can lead to an inside echo effect (called autophony) when the patient is talking. This disturbance can result in a bizarre talking voice and is extremely irritating, to the point where the patient will sometimes avoid talking altogether until the condition clears.
Rinsing is likely beneficial to most patients during the weeks or months following sinus or nasal surgery, regardless of the particular disease the patient has. The rinse removes blood clots, reduces the chance of infection, and helps to achieve normal breathing through the nose.  For this rinse, boiled or distilled water is needed. Once the patient is healed, only potable water is required. Greatest comfort and effect is obtained by using warm water whenever possible.