OPTIVAR
Clinical safety rating: caution
Comprehensive clinical and safety monograph for OPTIVAR (OPTIVAR).
Selective histamine H1-receptor antagonist; inhibits histamine release from mast cells and basophils, reducing allergic response.
| Metabolism | Hepatic via glucuronidation; minor CYP450 involvement. Elimination half-life: ~5-7 hours. |
| Excretion | Primarily renal excretion as unchanged drug (approximately 60-70% of administered dose is excreted unchanged in urine within 48 hours). The remainder is eliminated via biliary/fecal routes (30-40%), largely as unchanged drug with minor metabolites. |
| Half-life | Terminal elimination half-life: 6-9 hours in healthy adults; prolonged in renal impairment (up to 20-30 hours in severe renal insufficiency). |
| Protein binding | Approximately 70-80% bound to plasma proteins, primarily albumin. |
| Volume of Distribution | Volume of distribution: approximately 2.5-4.5 L/kg, indicating extensive extravascular distribution. |
| Bioavailability | Ophthalmic solution: Systemic bioavailability is low (less than 10% of administered dose) due to local administration and limited absorption; negligible oral bioavailability (drug is for topical ophthalmic use only). |
| Onset of Action | Ophthalmic solution: Onset of relief of ocular itching within minutes; peak effect at 30-60 minutes. |
| Duration of Action | Duration of action: 8-12 hours after a single dose, allowing twice-daily dosing for allergy symptom control. |
| Molecular Weight | 509.6 |
One drop (approximately 0.05 mL of 0.1% ophthalmic solution) in each affected eye twice daily, approximately every 6 to 8 hours.
| Dosage form | SOLUTION/DROPS |
| Renal impairment | No dose adjustment required for renal impairment based on current data. |
| Liver impairment | No dose adjustment required for hepatic impairment based on current data. |
| Pediatric use | Children 3 years and older: same as adult dose (one drop in each affected eye twice daily). Safety and efficacy in children under 3 years have not been established. |
| Geriatric use | No specific dose adjustment required; use same dose as for younger adults. Caution with concomitant medications and renal function as part of general geriatric care. |
| 1st trimester | No adequate studies in pregnant women. Use only if potential benefit justifies risk. Animal studies show no evidence of teratogenicity. |
| 2nd trimester | No adequate studies in pregnant women. Use only if potential benefit justifies risk. |
| 3rd trimester | No adequate studies in pregnant women. Use only if potential benefit justifies risk. |
Clinical note
Comprehensive clinical and safety monograph for OPTIVAR (OPTIVAR).
| Placental transfer | Not studied; molecular weight suggests potential crossing. |
| Breastfeeding | Not known if excreted in human milk. Caution should be exercised when administered to a nursing woman. |
| Lactation Rating |
■ FDA Black Box Warning
None.
| Common Effects | Hypoglycemia low blood glucose level Headache Nausea Diarrhea Flatulence |
| Serious Effects |
Hypersensitivity to azelastine or any component of the formulation
| Precautions | Avoid contact with soft contact lenses; contains benzalkonium chloride which may be absorbed by lenses., May cause transient burning/stinging upon instillation., Use with caution in patients with hepatic impairment. |
| Food/Dietary | No clinically significant food interactions. Alcohol may increase drowsiness; avoid or limit alcohol consumption as azelastine can cause central nervous system depression in some patients. |
Loading safety data…
| L3 (moderately safe) |
| Teratogenic Risk | Pregnancy Category B. No evidence of teratogenicity in animal studies; no adequate human studies. Risk cannot be ruled out; use only if clearly needed. |
| Fetal Monitoring | Monitor for maternal CNS depression, increased intraocular pressure, or cardiovascular effects. No specific fetal monitoring required. |
| Fertility Effects | No known adverse effects on fertility in animal studies; human data insufficient. |
| Clinical Pearls | OPTIVAR (azelastine hydrochloride) is a topical antihistamine approved for allergic conjunctivitis. Administer one drop in each affected eye twice daily. Inform patients that the dropper tip should not touch the eye or any surface to avoid contamination. The solution contains benzalkonium chloride, which may be absorbed by soft contact lenses; advise removing lenses before instillation and waiting at least 10 minutes before reinserting. Bitter taste may occur due to nasolacrimal drainage; patients can press on the tear duct (punctal occlusion) for 1 minute after instillation to minimize this. Onset of action is within minutes but maximal effect may take several days. |
| Patient Advice | Shake the bottle well before each use. · Remove contact lenses before using; wait at least 10 minutes before reinserting. · Do not touch the dropper tip to any surface or your eye. · Wait at least 5 minutes between other eye medications if using more than one. · You may experience a temporary bitter taste; pressing on the inner corner of the eye (near the nose) for 1 minute after the drop can help. · Do not use if the solution changes color or becomes cloudy. · Store at room temperature, away from light and moisture. |