What are the side effects of azelastine (antihistamine) nasal spray?

Common Side Effects of Azelastine Nasal Spray

The most common side effects of azelastine nasal spray include bitter taste, epistaxis (nosebleeds), somnolence (drowsiness), and headache. 1

Primary Side Effects

Azelastine nasal spray can cause several side effects, with varying frequencies depending on formulation and dosage:

Most Common Side Effects

• Bitter taste: Occurs in 8.4-19.7% of patients, depending on formulation and dose 1, 2, 3
• Epistaxis (nosebleeds): Reported in 3.2-5.1% of patients 1, 2
• Somnolence (drowsiness): Reported in 0.4-11.5% of patients, with higher rates at higher doses 1, 3
• Headache: Occurs in approximately 7.9% of patients 2
• Nasal irritation/rhinitis: Reported in 5.6-17% of patients 1, 2

Less Common Side Effects

• Dysesthesia (abnormal sensation): 7.9% 2
• Sinusitis: 3.2% 2
• Cough: 11.4% in pediatric patients 2
• Pharyngitis: Can occur at lower frequencies 2
• Post-nasal drip: Reported infrequently (<2%) 2

Dosage Impact on Side Effects

The incidence of side effects varies significantly based on dosage:

• At 1 spray per nostril twice daily:

  • Bitter taste: 8.3% 4
  • Somnolence: 0.4% 4

• At 2 sprays per nostril twice daily (standard dose):

  • Bitter taste: 19.7% 4
  • Somnolence: 11.5% 4

This demonstrates that lower doses can significantly improve tolerability while maintaining efficacy 4.

Formulation Differences

Different formulations of azelastine show varying side effect profiles:

• Azelastine 0.15% nasal spray: Bitter taste (8.4%), somnolence (1.7%) 3
• Azelastine 0.10% nasal spray: Bitter taste (9.4%), somnolence (0.6%) 3

Rare but Reported Side Effects

The FDA label reports several infrequent (<2%) side effects 2:

Cardiovascular

• Flushing
• Hypertension
• Tachycardia

Dermatological

• Contact dermatitis
• Eczema
• Skin infections

Neurological

• Hyperkinesia
• Hypoesthesia
• Vertigo

Psychological

• Anxiety
• Depression
• Sleep disorders

Respiratory

• Bronchospasm
• Throat burning
• Nasal dryness
• Laryngitis

Special Considerations

Pediatric Patients

Children may experience different side effect profiles, with higher rates of:

• Rhinitis/cold symptoms (17.0% vs 9.5% with placebo)
• Cough (11.4% vs 8.3%)
• Conjunctivitis (5.1% vs 1.8%) 2

Elderly Patients

Older adults may be more sensitive to the sedative effects of antihistamines, including azelastine, and should be monitored for psychomotor impairment 5.

Minimizing Side Effects

To reduce the incidence of side effects, especially bitter taste:

1. Use proper administration technique as recommended in product labeling 6
2. Consider lower doses when clinically appropriate (1 spray per nostril twice daily instead of 2 sprays) 4
3. For patients experiencing bitter taste with one formulation, trying an alternative formulation may be beneficial 1

Serious Adverse Events

While rare, the following serious adverse events have been reported during post-marketing surveillance 2:

• Anaphylactoid reactions
• Facial edema
• Dyspnea
• Paresthesia
• Vision abnormalities

If these occur, discontinuation of the medication is recommended.