Is long-term use of azelastine (antihistamine) nasal spray safe?

From the Guidelines

Azelastine nasal spray is generally considered safe for long-term use when used as directed, though it's best to use it under medical supervision. The typical recommended duration is for seasonal allergies (2-4 weeks) or perennial allergies (up to 6 months), with standard adult dosing being 1-2 sprays per nostril twice daily 1. Long-term safety studies have shown that azelastine maintains its effectiveness without significant tolerance development, and it has a good safety profile with minimal systemic absorption. The most common side effects include bitter taste, nasal irritation, and drowsiness, which often diminish with continued use 1. For extended use beyond the recommended periods, regular check-ups with a healthcare provider are important to monitor for rare complications like nasal septum damage or changes in effectiveness. Some patients may benefit from intermittent use during symptomatic periods rather than continuous administration, which can help minimize potential side effects while maintaining symptom control.

Key Considerations

• The safety profile of azelastine nasal spray is well-established, with minimal systemic absorption and a low risk of serious side effects 1.
• Common side effects, such as bitter taste and drowsiness, are generally mild and may decrease with continued use 1.
• Regular monitoring by a healthcare provider is recommended for extended use beyond the recommended periods to minimize the risk of rare complications.
• Intermittent use during symptomatic periods may be a suitable alternative to continuous administration for some patients, helping to balance symptom control with potential side effects.

Clinical Recommendations

• Azelastine nasal spray can be used as a first-line treatment for seasonal and perennial allergic rhinitis, with a recommended dosing of 1-2 sprays per nostril twice daily 1.
• Patients should be advised to use the medication as directed and to report any side effects or concerns to their healthcare provider.
• Regular follow-up appointments can help monitor the effectiveness of the treatment and minimize the risk of potential complications.
• The most recent study 1 supports the use of azelastine nasal spray in combination with other medications for the treatment of moderate to severe seasonal allergic rhinitis, further establishing its safety and efficacy in long-term use.

From the FDA Drug Label

CLINICAL PHARMACOLOGY Azelastine hydrochloride, a phthalazinone derivative, exhibits histamine H1 -receptor antagonist activity in isolated tissues, animal models, and humans. Pharmacodynamics In a placebo-controlled study (95 subjects with allergic rhinitis), there was no evidence of an effect of Astelin® Nasal Spray (2 sprays per nostril twice daily for 56 days) on cardiac repolarization as represented by the corrected QT interval (QTc) of the electrocardiogram

The long-term safety of azelastine nasal spray is not directly addressed in the provided drug labels. However, one study mentioned that Astelin® Nasal Spray was administered to 95 subjects with allergic rhinitis for 56 days without evidence of an effect on cardiac repolarization.

• Key points:
  • No direct information on long-term safety
  • One study with 56-day administration showed no effect on cardiac repolarization Based on the available information, no conclusion can be drawn about the long-term safety of azelastine nasal spray 2.

From the Research

Safety of Long-Term Azelastine Nasal Spray Use

• The long-term safety of azelastine nasal spray has been evaluated in several studies, including a 6-month study with a follow-up of up to 60 weeks 3.
• In this study, azelastine nasal spray was found to be well-tolerated, with approximately 96% of patients rating the tolerability of treatment as 'very good' or 'good' 3.
• The incidence of adverse events was low, with the most frequent events being application site reactions and bitter or unpleasant taste 3.
• No unwanted effects were reported by patients continuing treatment, and results of nasal biopsies indicated that azelastine nasal spray is a safe drug for long-term treatment of perennial allergic rhinitis 3.
• Another study evaluated the long-term safety of a novel intranasal formulation of azelastine hydrochloride and fluticasone propionate, and found that the incidence of treatment-related adverse events was low, with no evidence of late-occurring adverse events 4.
• Overall, the available evidence suggests that long-term use of azelastine nasal spray is safe and well-tolerated, with a low incidence of adverse events 3, 4.

Efficacy of Azelastine Nasal Spray

• Azelastine nasal spray has been shown to be effective in reducing nasal symptoms associated with seasonal allergic rhinitis, including nasal congestion, rhinorrhea, itchy nose, and sneezing 5, 6, 7.
• The efficacy of azelastine nasal spray has been compared to other treatments, including intranasal corticosteroids and oral antihistamines, and has been found to have a faster onset of action and a better safety profile 5.
• Azelastine nasal spray has also been shown to be effective in combination with fluticasone propionate, and may provide benefit for patients with difficult to treat seasonal allergic rhinitis 5.

Tolerability of Azelastine Nasal Spray

• Azelastine nasal spray has been found to be well-tolerated, with the most common adverse events being bitter taste and somnolence 6, 7.
• The incidence of bitter taste has been found to be lower with a dose of 1 spray per nostril twice daily compared to 2 sprays per nostril twice daily 6.
• Somnolence has been reported by a small percentage of patients treated with azelastine nasal spray, but the incidence is lower than with oral antihistamines 7.