Dorzolamide, sold under the brand name Trusopt among others, is medications used to treat high pressure inside the eye including glaucoma.[1] It is used as an eye drop.[1] Effects begin within three hours and lasts for at least eight hours.[1] It is also available as the combination dorzolamide/timolol.[1]

Clinical data
Trade namesTrusopt, others
  • US: C (Risk not ruled out)
Routes of
Topical (eye drops)
ATC code
Legal status
Legal status
Pharmacokinetic data
Protein binding~33%
Elimination half-life4 months
CAS Number
PubChem CID
CompTox Dashboard (EPA)
Chemical and physical data
Molar mass324.43 g·mol−1
3D model (JSmol)
 ☒N☑Y (what is this?)  (verify)

Common side effects include eye discomfort, eye redness, taste changes, and blurry vision.[1] Serious side effects include Steven Johnson syndrome.[1] Those allergic to sulfonamides may be allergic to dorzolamide.[1][2] Use is not recommended in pregnancy or breastfeeding.[2] It is a carbonic anhydrase inhibitor and works by decreasing the production of aqueous humour.[1]

Dorzolamide was approved for medical use in the United States in 1994.[1] It is available as a generic medication.[2] A 5 milliliter bottle in the United Kingdom costs the NHS less than £2 as of 2019.[2] In the United States the wholesale cost of this amount is about US$7.10.[3] In 2017, it was the 281st most commonly prescribed medication in the United States, with more than one million prescriptions.[4][5]

Medical usesEdit

Dorzolamide hydrochloride is used to lower excessive intraocular pressure in open-angle glaucoma and ocular hypertension.

Side effectsEdit

Ocular stinging, burning, itching and bitter taste.[6] It causes shallowing of the anterior chamber and leads to transient myopia.


It lowers IOP by about 20%.[6] 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.


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.[6]


  1. ^ a b c d e f g h i "Dorzolamide Hydrochloride Monograph for Professionals". American Society of Health-System Pharmacists. Retrieved 26 March 2019.
  2. ^ a b c d British national formulary : BNF 76 (76 ed.). Pharmaceutical Press. 2018. p. 1148. ISBN 9780857113382.
  3. ^ "NADAC as of 2019-02-27". Centers for Medicare and Medicaid Services. Retrieved 3 March 2019.
  4. ^ "The Top 300 of 2020". ClinCalc. Retrieved 11 April 2020.
  5. ^ "Dorzolamide Hydrochloride - Drug Usage Statistics". ClinCalc. Retrieved 11 April 2020.
  6. ^ a b c KD Tripari MD. Essentials of Medical Pharmacology (5th ed.). Jaypee Brothers Medical Publishers(P) Ltd. p. 88. ISBN 81-8061-187-6.

Further readingEdit