Dosing and uses of Trusopt (dorzolamide)
Adult dosage forms and strengths
ophthalmic solution
- 2%
Ocular Hypertension
Instill 1 gtt in affected eye(s) q8hr
Pediatric dosage forms and strengths
ophthalmic solution
- 2%
Ocular Hypertension
As in adults; 1 gtt in affected eye(s) q8hr
Trusopt (dorzolamide) adverse (side) effects
>10%
Ocular burning, stinging, discomfort (33%)
Bitter taste (25%)
Superficial punctate keratitis (10-15%)
Ocular allergic reactions (10%)
Frequency not defined
Blurred vision
Ocular dryness
Photophobia
Ocular redness
Tearing
Stevens-Johnson syndrome
Toxic epidermal necrolysis
Angioedema
Bronchospasm
Dyspnea
Epistaxis
Warnings
Contraindications
Hypersensitivity
Severe reanl impairment (CrCl<30 mL/min)
Cautions
Bacterial contamination can occur with multiple dose ophthalmic solutions and cause bacterial keratitis
Remove contact lenses, since the solution contains benzalkonium chloride which may be absorbed by some lenses
Absorbed systemically, potential risk of adverse effects similar to those for systemic sulfonamides (eg, Stevens-Johnson synd, blood dyscrasias, fulminant hepatic necrosis, and toxic necrolysis) may occur with ophthalmic use
Conjunctivitis and lid reactions reported with chronic administration (may resolve with discontinuation of drug therapy
Risk of corneal edema higher in patients with low endothelial cell counts; use catuion
Use concomitantly with oral carbonic anhydrase inhibitors not recommended
Pregnancy and lactation
Pregnancy category: C
Lactation: Not known whether distributed into breast milk; Do not nurse
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Trusopt (dorzolamide)
Mechanism of action
Sulfonamide and carbonic anhydrase inhibitor that reduces the secretion of hydrogen ion at renal tubule and increases excretion of bicarbonate, potassium, sodium, and water, which in turn decreases aqueous humor secretion
Pharmacokinetics
Absorption: Yes
Duration: 8-12hr
Peak effect: 2 hr
Onset of action: 2 hr
Half-life: 120 days
Peak Plasma: 24 mcg/g (cornea); 27 mcg/g (iris/ciliary body), 7.8 mcg/mL (aqueous humor)
Protein bound: 33% (to plasma proteins)
Metabolism: Liver, by cytochrome P450 isozymes to N-desethyldorzolamide
Excretion: Urine (80%)
