Dorzolamide

Dorzolamide, sold under the brand name Trusopt among others, is a medication used to treat high pressure inside the eye including glaucoma. It is used as an eye drop. Effects begin within three hours and lasts for at least eight hours. It is also available as the combination dorzolamide/timolol.
Common side effects include eye discomfort, eye redness, taste changes, and blurry vision. Serious side effects include Steven Johnson syndrome. Those allergic to sulfonamides may be allergic to dorzolamide. Use is not recommended in pregnancy or breastfeeding. It is a carbonic anhydrase inhibitor and works by decreasing the production of aqueous humour.
Dorzolamide was approved for medical use in the United States in 1994. It is available as a generic medication. In 2017, it was the 281st most commonly prescribed medication in the United States, with more than one million prescriptions.
Medical uses.
Dorzolamide hydrochloride is used to lower excessive intraocular pressure in open-angle glaucoma and ocular hypertension.
Side effects.
Ocular stinging, burning, itching and bitter taste. It causes shallowing of the anterior chamber and leads to transient myopia.
Pharmacodynamics.
It lowers IOP by about 20%. Carbonic Anhydrase can convert H2CO3 into HCO3 (bicarbonate) and H+. The H+ is then exchanged for sodium (Na) which allows you to make aqueous humor. By blocking carbonic anhydrase, the Na/H exchanger can't work, which will decrease Na in the cell and prevent aqueous humor production.
History.
This drug, developed by Merck, was the first drug in human therapy (market introduction 1995) that resulted from structure-based drug design. It was developed to circumvent the systemic side effects of acetazolamide which has to be taken orally.