Brimonidine Tartrate + Timolol Maleate

Generic Details

Generic Name

Brimonidine Tartrate Timolol Maleate

Other Names

  • Combigan
  • Simbrinza

Drug Class

  • Alpha agonist and beta blocker combination

Chemical Formula

C11H10BrN5O4 (Brimonidine Tartrate) C13H24N4O3S (Timolol Maleate)

Molecular Weight

442.22 g/mol (Brimonidine Tartrate) 432.44 g/mol (Timolol Maleate)

Mechanism of Action

  • Brimonidine reduces aqueous humor production and increases uveoscleral outflow, while timolol reduces aqueous humor production by blocking beta-adrenergic receptors

Indications

  • Glaucoma
  • Ocular hypertension

Common Dosage Forms

  • Eye drops

Typical Dosage

  • 1 drop in the affected eye(s) twice a day

Pediatric Dosage

  • Safety and efficacy not established in children under 2 years

Geriatric Dosage

  • Use with caution due to increased risk of systemic side effects

Side Effects

  • Burning/stinging/itching/redness of the eye
  • Blurred vision
  • Dry eyes
  • Headache
  • Dizziness

Contraindications

  • Hypersensitivity to any component of the product
  • Sinus bradycardia
  • Second- or third-degree AV block
  • Severe COPD
  • Asthma

Pregnancy Category

  • C - Use with caution

Lactation Safety

  • Use with caution as systemic absorption is possible

Drug Interactions

  • Beta-blockers, calcium channel blockers, digoxin

Overdose Symptoms

  • Hypotension
  • Bradycardia
  • Bronchospasm

Antidote for Overdose

  • No specific antidote, symptomatic and supportive treatment

Storage Conditions

  • Store at 15°C to 25°C (59°F to 77°F)
  • Protect from light

Pharmacokinetics

  • Absorption: Brimonidine: Rapidly absorbed through the cornea; Timolol: Absorbed systemically
  • Distribution: Both drugs distribute into various tissues
  • Metabolism: Brimonidine: Hepatic; Timolol: Hepatic
  • Excretion: Primarily renal for both drugs

Precautions

  • Monitor for changes in heart rate and blood pressure
  • Caution in patients with cardiovascular disease
  • Do not touch dropper tip to avoid contamination

Warnings

  • May mask hypoglycemia symptoms in diabetic patients
  • May potentiate systemic beta-blockade

Others

  • Avoid in patients with depression or psychiatric disorders
  • Regular eye examinations recommended during treatment period