Rhinitis is inflammation of the mucous lining inside the nose, resulting in a runny nose, sneezing, and nasal congestion. While these symptoms are often associated with allergies or the common cold, certain medications can also cause them as a side effect. This condition is known as drug-induced rhinitis, a specific type of non-allergic rhinitis that is neither caused by an immune response nor an infection. Recognizing that a medication is the source of ongoing nasal discomfort is the first step toward finding relief.
Common Medication Classes That Cause Rhinitis
Many systemic drug classes can cause nasal symptoms, often by affecting the balance of nasal blood vessels. Antihypertensive medications used to manage high blood pressure are among the most common culprits. Angiotensin-Converting Enzyme (ACE) inhibitors, such as lisinopril or enalapril, frequently cause persistent rhinitis and postnasal drainage. This side effect is distinct from the well-known ACE inhibitor cough but shares a similar underlying mechanism.
Other blood pressure medications, including beta-blockers like carvedilol, can also lead to nasal blockage. Alpha-adrenergic antagonists, sometimes used to treat benign prostatic hyperplasia, may similarly trigger symptoms. Nonsteroidal anti-inflammatory drugs (NSAIDs) like aspirin and ibuprofen may cause acute nasal reactions in susceptible individuals. This reaction is often part of Aspirin-Exacerbated Respiratory Disease (AERD), which involves chronic rhinosinusitis and nasal polyps.
Several other medication classes have been linked to nasal congestion:
- Certain psychiatric medications, including some antidepressants and antipsychotics.
- Phosphodiesterase-5 (PDE5) inhibitors, commonly used for erectile dysfunction.
- Hormonal medications, such as oral contraceptives or exogenous estrogens, due to estrogen receptors within the nasal lining.
A different form of drug-induced rhinitis, called rhinitis medicamentosa, is caused by the overuse of topical decongestant nasal sprays (e.g., oxymetazoline), leading to a rebound congestion effect.
How Medications Trigger Nasal Congestion
The congestion caused by systemic medications results from an alteration of the physiological processes that control the nasal passages. One major mechanism involves the accumulation of bradykinin, which is a potent vasodilator and inflammatory peptide. ACE inhibitors block the enzyme that typically breaks down bradykinin, leading to its buildup in the airways. This excess bradykinin causes local inflammation and increased vascular permeability in the nasal mucosa, resulting in swelling and a runny nose.
Another common pathway involves the disruption of the autonomic nervous system, which regulates the size of blood vessels in the nose. The nasal lining contains numerous blood vessels normally kept slightly constricted by the sympathetic nervous system. Medications that block or reduce this sympathetic tone, such as beta-blockers, cause the nasal blood vessels to widen. This widening, or vasodilation, causes the tissue to swell, leading to nasal blockage and congestion.
The effect of NSAIDs and aspirin is distinct, often involving a change in the balance of inflammatory mediators. In sensitive patients, these drugs inhibit the cyclooxygenase-1 (COX-1) enzyme, which shifts the body toward overproducing leukotrienes. Leukotrienes are powerful inflammatory molecules that cause significant bronchoconstriction and nasal congestion, leading to acute and severe rhinitis symptoms.
Practical Steps for Managing Drug-Induced Symptoms
If nasal symptoms are noticed after starting a new medication, consider the possibility of drug-induced rhinitis. The most important step is to consult the prescribing physician before making any changes to the drug regimen. Suddenly stopping a necessary medication, especially for conditions like high blood pressure, can be dangerous.
The physician may recommend discontinuing the suspected drug or switching to an alternative drug class that achieves the same therapeutic effect without the nasal side effect. While the medication is being managed, temporary relief can be found through simple symptomatic treatments.
Intranasal saline sprays or rinses can help flush the nasal passages and provide moisture. In some cases, a doctor may suggest a trial of an intranasal corticosteroid spray or an intranasal antihistamine to reduce inflammation and congestion. However, the definitive treatment remains the identification and modification of the causative medication under medical supervision.