What is rhinitis medicamentosa?
Rhinitis medicamentosa is nasal congestion and sneezing that arises with the overuse of medication for treating nasal symptoms. This is also known as rebound rhinitis. Although this is a short-lived reaction in some cases, it can have permanent effects such as chronic sinusitis. Typically the overuse stems from a pre-existing chronic nasal problem and eventually the patient believes that the underlying problem is worsening. This compels a person to continue using the nasal decongestant and sometimes even increasing the dosage on their own, thereby further aggravating the condition.
Rhinitis Medicamentosa Incidence
The condition affects about 1 to 7 out of 100 people based on surveys conducted with allergists and otolaryngologists. However, the incidence could be much higher as overuse may be underreported by patients. With decongestant use being unregulated compared to other drugs, there may also be a misconception that it is harmless and therefore it is not mentioned to doctors. Men and women are affected equally and the highest incidence is among young and middle-aged adults.
Rhinitis Medicamentosa Other Names
Rhinitis medicamentosa is also known as rebound rhinitis. Various other medication can cause nasal symptoms even if these drugs were not intended to initially treat a nasal problem. In this case it is broadly known as drug-induced rhinitis. In fact the term drug-induced rhinitis can be used for all these instances whether it was induced by nasal decongestants or other medication. The term chemical rhinitis can also be ascribed to rhinitis medicamentosa although this can also mean non-pharmaceutical airborne irritants like fumes and gases with air pollution and industrial exhausts.
Rhinitis Medicamentosa Pathophysiology
Normal nasal mucosa
The nasal mucosa is a thin lining of the nasal cavity which extends into the paranasal sinuses. All of the mucus within the nose and sinuses are from the nasal mucosa, although small amounts of fluid (tears) can drain from the eyes. The nasal mucosa has a rich supply of minute blood vessels. When the parasympathetic nerves stimulate the area through the action of aceytlcholine, the blood flow to the mucosa increases and more mucus is produced. Conversely, the sympathetic nerves decrease blood flow to the mucosa and reduces nasal secretions by the action of norepinephrine.
There are other local factors that can affect the mucus production in the nose. This includes the immune cells and associated chemicals. When secreted and activated, these cells and chemicals can induce a similar reaction. Blood flow and mucus production increases accordingly. Overactivity will therefore lead to excessive mucus production and secretion. The consistency may also change thereby making the mucus more thicker and sticky or thinner and watery.
Effect of decongestants
There are two types of nasal decongestants which work in slightly different ways to reduce nasal mucus discharge. The first is sympathomimetic amines like benzedrine, ephedrine and pseudoephedrine. It stimulates the sympathetic nerves to release norepinephrine which then reduces blood flow to the nasal mucosa and nasal mucus discharge. The second is imidazolines like clonidine, naphazoline and oxymetazoline. It acts on the same receptors as norepinephrine thereby reducing nasal mucus dicharge. Other substances like benzalkonium chloride are preservatives in decongestants. It may not have any therapeutic effect but could possibly contribute to rhinitis medicamentosa.
Rebound rhinitis process
Rebound rhinitis is more likely to arise from one or more of the following actions :
- Reduced norepinephrine secretion which normally decreases mucus production.
- Greater acetylcholine secretion by increased activity of the parasympathetic nerves.
- Prolonged stimulation of certain receptors (beta-adrenoreceptors) that eventually causes swelling of the nasal mucosa.
- Increased blood flow and greater permeability of the blood vessels.
How do decongestants cause rebound rhinitis?
The exact process behind rebound rhinitis is not fully understood.
- Sympathomimetics may therefore contribute to rebound rhinitis by weakly stimulating the beta-adrenoreceptors.
- Imidazolines can lead to reduced norepinephrine secretion by disrupting the negative feedback mechanism.
- Benzalkonium chloride may damage the nasal mucosa or exacerbate existing rebound rhinitis.
Rhinitis Medicamentosa Causes
Rhinitis medicamentosa is caused by various drugs and other substances, either inhaled or taken orally. Sometimes physiological conditions like pregnancy and the onset of puberty can cause hormonal changes which may trigger rhinitis. It can worsen a pre-existing case of rhinitis and therefore be mistaken for rhinitis medicamentosa.
Nasal decongestants are the main cause of rebound rhinitis. These substances are used to treat nasal congestion, runny nose (rhinorrhea) and sneezing caused by conditions such as :
- allergic and non-allergic rhinitis (usually not infectious)
- C-PAP machine usage
- chronic rinhitis and sinusitis (rhinosinusitis)
- nasal polyps
- rhinitis following rhinoplasty (cosmetic surgery to the nose)
- upper respiratory tract infections
It is important to note that these conditions are not the cause of rebound rhinitis but rather the reason for using, and misusing, nasal decongestants.
- Various antihypertensives (high blood pressure medication).
- Beta-blockers used for hypertension and other conditions.
- Phosphodiesterase type 5 (PDE5) inhibitors for erectile dysfunction.
- Hormone replacement therapy for menopause.
- Oral contraceptives to prevent pregnancy.
- Antidepressants and antipsychotics for various mental health disorders.
- Non-steroidal anti-inflammatory drugs (NSAIDs) for pain and inflammation.
- Gabapentin for epilepsy and sometimes for neuropathic pain.
Cocaine may also cause rebound rhinitis due to its local chemical effects when snorted. Tobacco sniffing (snuff) may cause some degree of irritant rhinitis.
Rhinitis Medicamentosa Symptoms
- Nasal congestion but no runny nose (rhinorrhea).
- Red and inflamed nasal mucosa
- Mouth breathing
- Sleep apnea
- Sore throat
- Dry mouth
Rhinitis Medicamentosa Diagnosis
Diagnosing rhinitis medicamentosa depends on the symptoms present, exclusion of other conditions that may cause these symptoms and confirming prolonged use of nasal decongestants.
Duration of use
Patients will report using a nasal decongestant, whether over-the-counter or prescribed, for periods exceeding 4 to 6 weeks. Misuse where there is excessive use often beyond the directions of use are typically reported. Patients may do so in an attempt to counteract the worsening symptoms.
Various tests from blood tests, to skin allergy testing, CT scans and examination of the nasal mucosa sample collected during a biopsy may be utilized to exclude conditions that typically present with these symptoms.
Rhinitis Medicamentosa Complications
The nasal mucosa may enlarge and cells may multiply as a complication of rebound rhinitis. Excessive nasal mucus discharge may therefore continue even after nasal decongestants have been stopped for long periods of time. In severe cases, there may be a “hole” in the septum dividing the cavities (perforated nasal septum). Chronic rhinosinusitis and atrophic rhinitis may arise as a complication of rhinitis medicamentosa. There may be recurrent episodes of acute sinusitis due to infections.
Rhinitis Medicamentosa Treatment
Weaning and withdrawal
The key to treating rhinitis medicamentosa is to discontinue the use of nasal decongestants. Complications, if present, can be treated thereafter except for infections which need immediate treatment. Ideally a patient should stop using the nasal decongestant immediately (withdrawal) but this is often not possible. Instead gradual weaning by reducing the dosage over a period of time will allow the patient to cope better. However, even in these cases the persistence of symptoms thereafter and a dependence on the short-term relief offered by the nasal decongestant compels a person to use it again.
Corticosteroids may prove to be a useful adjunct during the weaning and withdrawal phase. Nasal corticosteroids sprays or even oral corticosteroids can be used for a period of time. However, weaning off corticosteroids is also important as sudden discontinuation can cause a secondary exacerbation of the symptoms. Systemic decongestants may also be useful during this period. Non-medicated saline/aqueous sprays and washes may be helpful but often patients ascribe the exacerbation of symptoms to these products and refuse to use it thereafter. Education on rhinitis medicamentosa is therefore important to compel patients to break the habit of using nasal decongestants.
Treatment measures may differ for rhinitis associated with the use of a C-PAP machine and in newborns. However, this should be overseen by an otorhinolaryngologist and pediatrician. No changes should be made without medical advice, especially in these patients. Surgery may be measured as deemed necessary by an otorhinolaryngologist and allergist :
- Nasal polypectomy for the surgical removal of polyps.
- Septoplasty to correct a deviated septum.
- Submucosal destruction and turbinate reduction to remove tissue that may be overgrown and increasing copious amounts of mucus.