Usage
Brimonidine + Stabilized Oxychloro ophthalmic solution is prescribed to lower intraocular pressure (IOP) in patients with open-angle glaucoma or ocular hypertension. It is classified as an ocular antihypertensive agent, specifically an alpha-2 adrenergic agonist. Brimonidine’s mechanism of action involves reducing aqueous humor production and increasing uveoscleral outflow. The stabilized oxychloro complex acts as a preservative.
Alternate Names
Brimonidine tartrate + Stabilized oxychloro complex is the generic name. Brand names include Alphagan P, Alphagan Z, and Brimonidine Tartrate Ophthalmic Solution.
How It Works
Pharmacodynamics: Brimonidine, an alpha-2 adrenergic agonist, primarily lowers IOP by reducing aqueous humor production and increasing uveoscleral outflow. It binds to alpha-2 adrenergic receptors in the ciliary body, decreasing cAMP production and subsequently aqueous humor formation.
Pharmacokinetics: Brimonidine is absorbed relatively quickly after topical ocular administration, reaching peak concentrations in the aqueous humor within one to two hours. It undergoes minimal metabolism in ocular tissues and is primarily eliminated unchanged through renal excretion. A small portion is metabolized in the liver. Stabilized oxychloro complex, upon light exposure, dissipates into natural tear components (sodium and chloride ions, oxygen, and water).
Dosage
Standard Dosage
Adults: One drop in the affected eye(s) three times daily, approximately 8 hours apart.
Children: Use is not recommended for children younger than 2 years old. For children 2 years and older, the recommended dose is the same as for adults: one drop in the affected eye(s) three times daily, approximately 8 hours apart. However, children should be monitored closely for potential side effects, such as apnea, bradycardia, and hypotension.
Special Cases:
- Elderly Patients: No dosage adjustment is generally necessary.
- Patients with Renal Impairment: Caution is advised, and monitoring is recommended.
- Patients with Hepatic Dysfunction: Caution is advised, and monitoring is recommended.
- Patients with Comorbid Conditions: Use with caution in patients with cardiovascular disease, depression, or cerebrovascular insufficiency.
Clinical Use Cases
The dosage remains consistent for all listed clinical scenarios (Intubation, Surgical Procedures, Mechanical Ventilation, Intensive Care Unit (ICU) Use, Emergency Situations) as it’s specifically for managing chronic conditions, glaucoma and ocular hypertension, rather than acute events.
Dosage Adjustments
Dosage adjustments may be necessary for patients with renal or hepatic impairment. Close monitoring of these patients is recommended.
Side Effects
Common Side Effects:
- Ocular: Blurred vision, eye redness, burning or stinging, foreign body sensation, itching, dry eye.
- Systemic: Dry mouth, headache, fatigue, drowsiness.
Rare but Serious Side Effects:
- Apnea, bradycardia, hypotension (especially in infants).
- Allergic reactions (e.g., eyelid swelling, itching, rash).
Long-Term Effects:
- Potential for worsening of dry eye with prolonged use.
Adverse Drug Reactions (ADR):
- Severe allergic reactions (e.g., anaphylaxis).
- Severe hypotension or bradycardia.
Contraindications
- Hypersensitivity to brimonidine or any component of the formulation.
- Patients receiving monoamine oxidase (MAO) inhibitor therapy.
- Neonates and infants (children under 2 years of age).
Drug Interactions
- MAO inhibitors: Concomitant use is contraindicated.
- CNS depressants (e.g., alcohol, barbiturates, opiates): May potentiate CNS depression.
- Tricyclic antidepressants: May diminish the hypotensive effect of brimonidine.
- Cardiac glycosides: Use with caution as the combination can increase the risk of bradycardia or hypotension.
Pregnancy and Breastfeeding
- Pregnancy Safety Category: B (Animal studies have not shown fetal harm, but there are no adequate studies in pregnant women). Brimonidine crosses the placenta. Use only if potential benefit outweighs the risk to the fetus.
- Breastfeeding: Brimonidine is excreted in breast milk. Use with caution. Consider discontinuing breastfeeding or using an alternative medication.
Drug Profile Summary
- Mechanism of Action: Alpha-2 adrenergic agonist; reduces aqueous humor production and increases uveoscleral outflow.
- Side Effects: Ocular irritation (e.g., burning, stinging, blurred vision), dry mouth, headache, fatigue. Rarely, apnea, bradycardia, hypotension.
- Contraindications: Hypersensitivity, MAO inhibitor use, neonates/infants.
- Drug Interactions: MAOIs, CNS depressants, tricyclic antidepressants, cardiac glycosides.
- Pregnancy & Breastfeeding: Category B; caution advised. Excreted in breast milk; caution advised.
- Dosage: 1 drop in the affected eye(s) three times daily (approximately every 8 hours).
- Monitoring Parameters: Intraocular pressure (IOP), heart rate, blood pressure (especially in infants and cardiovascular patients).
Popular Combinations
Brimonidine is often combined with timolol (a beta-blocker) for additive IOP-lowering effects. Fixed combinations of brimonidine/timolol are commercially available.
Precautions
- General Precautions: Patient evaluation for allergies, hepatic or renal impairment, cardiovascular disease, and concomitant medications is essential before starting treatment.
- Specific Populations:
- Pregnant Women: Use with caution. Weigh potential benefits against fetal risks.
- Breastfeeding Mothers: Monitor infants for adverse reactions; consider discontinuing breastfeeding or switching to an alternative medication.
- Children & Elderly: Closely monitor for potential side effects. Use is contraindicated in children under 2 years.
- Lifestyle Considerations: Patients experiencing drowsiness or blurred vision should avoid driving or operating machinery.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Brimonidine + Stabilized Oxychloro?
A: One drop in the affected eye(s) three times a day, about 8 hours apart.
Q2: Can Brimonidine + Stabilized Oxychloro be used in children?
A: It is contraindicated in children under 2 years old. Use with caution and close monitoring in children older than 2 years.
Q3: What are the common side effects of Brimonidine + Stabilized Oxychloro?
A: Common side effects include blurred vision, eye redness, burning or stinging, foreign body sensation, dry mouth, headache, fatigue, and drowsiness.
Q4: Are there any serious side effects I should be aware of?
A: Rare but serious side effects include apnea, bradycardia, hypotension (especially in infants), and allergic reactions.
Q5: What medications should be avoided while taking Brimonidine + Stabilized Oxychloro?
A: Avoid concomitant use with MAO inhibitors. Use with caution with CNS depressants, tricyclic antidepressants, and cardiac glycosides.
Q6: Can I use Brimonidine + Stabilized Oxychloro if I am pregnant or breastfeeding?
A: Use during pregnancy only if the potential benefit outweighs the potential risk to the fetus. If breastfeeding, use with caution; consider discontinuing breastfeeding or switching to an alternative.
Q7: How does Brimonidine + Stabilized Oxychloro interact with alcohol?
A: Alcohol may enhance the CNS depressant effects of brimonidine. Caution is advised.
Q8: What should I do if I miss a dose?
A: Instill the missed dose as soon as you remember, unless it’s close to the next scheduled dose. Do not double the dose.
A: Remove contact lenses before instilling the eye drops and wait at least 15 minutes before reinserting them.
