Pharmacologic class (EPC) · 12 drug pages

Carbonic anhydrase inhibitor: adverse event reports filed with FDA

19,384 reports list a drug in this class as a suspect or interacting product, 2004–2026.

Read first · FDA's statement on these data

Adverse event reports submitted to FDA do not undergo extensive validation or verification. Therefore, a causal relationship cannot be established between product and reactions listed in a report. While a suspected relationship may exist, it is not medically validated and should not be the sole source of information for clinical decision making or other assumptions about the safety or efficacy of a product. Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product. openFDA, FDA

FDA adds: "There is no certainty that the reported event (adverse event or medication error) was actually due to the product. FDA does not require that a causal relationship between a product and event be proven, and reports do not always contain enough detail to properly evaluate an event." The information in these reports "cannot be used to estimate the incidence of these events."

Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated.

Not medical advice. This site counts what was reported to FDA. Questions about a medicine or device belong with a pharmacist or clinician.

19,384
reports across the class: 0.1% of all reports; 766
reports, 12 months to June 2026: 894 in the 12 months before; 40.1%
marked serious by the reporter: 57.4% across all reports; 12
drugs with a page: brand and generic names counted separately

Carbonic anhydrase inhibitor is a pharmacologic class (an FDA Established Pharmacologic Class) with 12 drug pages on this site. Together those drugs are listed as a suspect or interacting product in 19,384 adverse event reports received by FDA, 0.1% of the database, from January 2004 to June 2026.

766 reports arrived in the 12 months to June 2026, down 14% from 894 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. 40.1% of the class's reports are marked serious, 4.9% record death among the outcomes and 11.5% record hospitalisation, as reported.

Across the class the reactions recorded most often are treatment failure (21.7%), drug ineffective (9.3%) and eye irritation (7.1%). The class median share shown beside each term is the middle value across the member drugs; it is the comparison used on every drug page in this class.

The members table is ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Drugs in the class

Drug	Name type	Reports	Latest 12 months	Marked serious	Top term recorded
AzoptBrinzolamide	brand	3,656	40	37.5%	Treatment failure
SimbrinzaBrinzolamide/brimonidine tartrate	brand	2,953	64	33.9%	Treatment failure
Acetazolamide	generic	2,567	259	87.3%	Drug ineffective
Dorzolamide	generic	2,073	75	18.2%	Treatment failure
Cosopt PfDorzolamide hydrochloride and timolol maleate	brand	1,880	12	19.7%	Eye irritation
KeveyisDichlorphenamide	brand	1,559	41	27.2%	Paraesthesia
CosoptDorzolamide hydrochloride and timolol maleate	brand	1,347	30	66.9%	Eye irritation
Brinzolamide	generic	886	66	73%	Dizziness
Dorzolamide hydrochloride	generic	692	72	32.2%	Treatment failure
Dorzolamide hcl	generic	688	0	2.8%	Treatment failure
Dorzolamide and TimololDorzolamide hydrochloride and timolol maleate ophthalmic solution	brand	562	4	11.4%	Treatment failure
Dorzolamide hydrochloride timolol maleate	generic	521	103	25%	Eye irritation

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Reports by month, five years

FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

Reactions recorded across the class

share of class reports recording the termmedian drug in the class

Treatment failurethe treatment did not work21.7%4,215
Drug ineffectivethe medicine did not work as expected9.3%1,803
Eye irritationeye irritation7.1%1,378
Ocular hyperaemiaa red eye5.8%1,117
Eye paineye pain4.8%923
Vision blurredblurred vision4.5%871
Hypersensitivityan allergic-type reaction4.2%812
Dizzinesslight-headedness or unsteadiness3.9%756
Dyspnoeashortness of breath3.7%713
Off label useused for a purpose or in a way not on the label3.6%701
Fatiguetiredness3.5%682
Intraocular pressure increasedraised pressure in the eye3.4%658
Headachehead pain3.2%613
Eye pruritus2.9%571
Nauseafeeling sick2.4%459
Astheniaweakness or lack of energy2.3%449
Visual impairmentreduced vision2.3%443
Blindnessloss of sight2.2%425
Malaisegeneral feeling of being unwell2.1%413
Falla fall2.1%412
Glaucomaraised pressure in the eye2.1%404
Paraesthesiatingling or pins and needles2%397
Somnolencedrowsiness2%395
Condition aggravatedthe condition being treated got worse1.9%376
Diarrhoealoose or frequent stools1.8%357

Solid bar: share of all class reports. Hollow bar: the median share across the 12 member drugs, the reference used on each member's page. One report can record several terms.

Outcomes, patients and reporters

Outcomes recorded

Death4.9%942

Life-threatening1.6%313

Hospitalisation (initial or prolonged)11.5%2,237

Disability1.6%311

Congenital anomaly0.3%66

Other serious29.6%5,735

Not serious59.9%11,618

Patient age

Under 20.5%94

2 to 110.7%143

12 to 171.2%223

18 to 446.1%1,181

45 to 648.3%1,607

65 to 747.9%1,525

75 and over12.2%2,373

Age not given63.1%12,238

Who reported

Physician15.9%3,073

Pharmacist5.4%1,045

Other health professional19.3%3,745

Lawyer0%9

Consumer or non-health professional52.8%10,232

Not given6.6%1,280

Grey bar: all 20,646,523 reports in the database. Outcome flags are as the reporter set them and are not verified by FDA.

Questions about Carbonic anhydrase inhibitor reports

Which drugs are in the Carbonic anhydrase inhibitor class on this site?

Azopt, Simbrinza, Acetazolamide, Dorzolamide, Cosopt Pf and Keveyis and 6 more. Class membership comes from the pharmacologic class (EPC) on the drug's FDA label.

How many reports does the class have?

19,384 reports through June 2026, 766 of them in the latest 12 months. A report listing two drugs of the class counts once for each.

What reactions are recorded most often?

treatment failure (21.7%), drug ineffective (9.3%), eye irritation (7.1%), ocular hyperaemia (5.8%) and eye pain (4.8%).

Can the members table be used to rank the drugs?

No. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." Drugs differ in how many people take them, in the conditions they treat, in time on the market and in how diligently reports are collected.

How do I report an adverse event?

Through FDA MedWatch (Form FDA 3500, or 1-800-FDA-1088) or to the manufacturer. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A class is the Established Pharmacologic Class most often attached to a drug's reports by openFDA's label harmonisation, or from the NDC Directory where reports carry none. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.