Trusopt is an ophthalmic medication marketed under the brand name Trusopt. It contains dorzolamide as its active ingredient and is supplied as a 2 % ophthalmic solution in a bottle. Dorzolamide belongs to the class of carbonic anhydrase inhibitors and is used to lower intra-ocular pressure (IOP) in certain eye disorders. In Hong Kong, Trusopt is classified as a prescription-only medication and is regulated by the Hong Kong Department of Health. The product is also approved by the U.S. Food and Drug Administration (FDA) for the same indications.
Dorzolamide inhibits the enzyme carbonic anhydrase in the ciliary body of the eye. By blocking this enzyme, the production of aqueous humor-the fluid that fills the front part of the eye-is reduced. Lower aqueous-humor production leads to a decrease in intra-ocular pressure, which is the primary therapeutic goal in conditions such as open-angle glaucoma and ocular hypertension. The onset of IOP-lowering effect typically occurs within a few hours after instillation, and the pressure-reducing effect can last for up to 12 hours, supporting once- or twice-daily dosing.
Trusopt is FDA- and Hong Kong-approved for the following ophthalmic indications:
The medication may be used alone or in combination with other IOP-lowering agents (e.g., prostaglandin analogues, beta-blockers) when monotherapy does not achieve target pressure levels.
No robust peer-reviewed evidence currently supports off-label uses of dorzolamide ophthalmic 2 % that would meet the required standard for inclusion. Healthcare professionals should rely on approved indications and consider any experimental use only under specialist supervision and after a thorough risk-benefit assessment.
Absolute contraindications
Relative contraindications and cautions
Special populations
These effects are generally mild and often diminish with continued use.
If any serious reaction occurs, discontinue the medication and seek urgent care.
Patients should inform their ophthalmologist or pharmacist of all eye drops, oral medications, supplements, and herbal products they are using.
Regular follow-up with an ophthalmologist is essential to adjust therapy and to detect any adverse effects early.
This article provides educational information about Trusopt and is not a substitute for professional medical advice. Treatment decisions, including use for unapproved indications, must be made under the guidance of a qualified healthcare provider. The content is intended for informational purposes and does not constitute medical recommendations. Always consult a physician before starting, stopping, or changing any medication regimen.
Yes. The typical regimen involves instilling one drop in each affected eye. If only one eye requires treatment, the medication can be applied solely to that eye as directed by the ophthalmologist.
Contact your eye clinic or pharmacy promptly to obtain a refill. Do not attempt to reuse a partially emptied bottle or transfer the solution to another container, as sterility cannot be guaranteed.
Contact lenses should be removed before instilling the drops and reinserted at least 15 minutes later to avoid trapping the medication against the cornea, which could cause irritation.
After opening, the solution remains stable for 30 days when stored at room temperature and kept tightly sealed. Discard any remaining drops after this period, even if the expiry date on the label has not been reached.
Transient blurred vision can occur immediately after instillation, but it usually resolves within a few minutes. Avoid driving or operating heavy machinery until your vision clears.
Most over-the-counter lubricating drops are compatible, but avoid simultaneous use of other carbonic anhydrase inhibitor eye drops. Space applications by a few minutes to prevent wash-out.
No. Dorzolamide does not affect iris pigmentation. Changes in eye colour are more commonly associated with certain prostaglandin analogues, not with carbonic anhydrase inhibitors.
Because dorzolamide is a sulfonamide that is excreted unchanged in the urine, patients with a history of renal calculi should discuss risks with their clinician, especially if they are also taking systemic carbonic anhydrase inhibitors.
Yes, but keep the bottle in its original packaging, include a copy of the prescription, and ensure it complies with the import regulations of the destination country. Some airlines restrict liquids over 100 ml in carry-on luggage; pack the bottle in checked baggage if needed.
Topical dorzolamide has minimal systemic absorption, so it typically does not affect systemic blood pressure. However, patients on multiple systemic carbonic anhydrase inhibitors should be monitored for potential additive effects.
