Reported Reactions

Drugs › Carbonic anhydrase inhibitor

Brand name · Dorzolamide hydrochloride and timolol maleate

Cosopt Pf: adverse event reports filed with FDA

1,880 reports list it as a suspect or interacting product, 2012–2026. Class: Carbonic anhydrase inhibitor.

1,880
reports as suspect product
0% of all reports · about 137 a year
12
reports, 12 months to June 2026
17 in the 12 months before
19.7%
marked serious by the reporter
40.1% across the class
16%
record death among outcomes, as reported
300 reports · not verified by FDA

1,880 adverse event reports received by FDA list the brand name Cosopt Pf (dorzolamide hydrochloride and timolol maleate) as a suspect or interacting product, from October 2012 to April 2026. A further 167 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 12 reports listed it, down 29% from 17 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 137 reports a year and 0% of the 20,646,523 reports in the database, and 9.7% of the reports for the carbonic anhydrase inhibitor class. How many people take it is not in the data, so a count is not a rate of occurrence.

The reactions recorded most often are eye irritation (23.7%), ocular hyperaemia (21.9%) and eye pruritus (15.4%). A report can list several reactions, so shares add to more than 100%; 182 different terms appear across these reports. Eye irritation is recorded in 23.7% of these reports, a larger share than in the median carbonic anhydrase inhibitor drug (4.7%).

19.7% of the reports are marked serious by the reporter (40.1% across the class); 16% record death among the outcomes and 1.5% record hospitalisation, as reported. 45.3% of the reports came from consumers, and the largest patient age group is 75 and over (17.5%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

062123Jul 2021: 22Aug 2021: 23Sep 2021: 9Oct 2021: 19Nov 2021: 17Dec 2021: 222022Jan 2022: 23Feb 2022: 22Mar 2022: 32Apr 2022: 20May 2022: 19Jun 2022: 15Jul 2022: 10Aug 2022: 2Sep 2022: 1Oct 2022: 1Nov 2022: 1Dec 2022: 02023Jan 2023: 0Feb 2023: 1Mar 2023: 1Apr 2023: 123May 2023: 2Jun 2023: 0Jul 2023: 0Aug 2023: 0Sep 2023: 0Oct 2023: 0Nov 2023: 0Dec 2023: 02024Jan 2024: 0Feb 2024: 0Mar 2024: 0Apr 2024: 5May 2024: 0Jun 2024: 1Jul 2024: 0Aug 2024: 1Sep 2024: 2Oct 2024: 3Nov 2024: 0Dec 2024: 02025Jan 2025: 0Feb 2025: 11Mar 2025: 0Apr 2025: 0May 2025: 0Jun 2025: 0Jul 2025: 0Aug 2025: 0Sep 2025: 0Oct 2025: 0Nov 2025: 0Dec 2025: 02026Jan 2026: 0Feb 2026: 10Mar 2026: 0Apr 2026: 2May 2026: 0Jun 2026: 0

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

02525042012: 120122013: 982014: 2520142015: 22016: 4920162017: 1302018: 11320182019: 4022020: 50420202021: 2482022: 14620222023: 1272024: 1220242025: 112026: 122026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Cosopt Pf reports recording the termmedian drug in carbonic anhydrase inhibitor

  1. Eye irritationeye irritation23.7%445
  2. Ocular hyperaemiaa red eye21.9%411
  3. Eye pruritus15.4%289
  4. Deaththe patient died; cause not stated by this term10.6%199
  5. Eye swellinga swollen eye9.5%179
  6. Eye paineye pain8.5%159
  7. Lacrimation increasedwatery eyes6.1%114
  8. Vision blurredblurred vision5.5%103
  9. Drug ineffectivethe medicine did not work as expected4%76
  10. Hypersensitivityan allergic-type reaction3.4%64
  11. Product quality issuea problem with the product itself2.7%51
  12. Dizzinesslight-headedness or unsteadiness2.5%47
  13. Dry eyedry eye2.4%46
  14. Dyspnoeashortness of breath2.2%42
  15. No adverse eventno adverse event was reported1.9%36
  16. Headachehead pain1.9%35
  17. Drug dose omissiona dose was missed1.6%31
  18. Erythemaskin redness1.6%31
  19. Eye injury1.5%29
  20. Intraocular pressure increasedraised pressure in the eye1.5%28
  21. Eye burns1.3%25
  22. Fatiguetiredness1.3%24
  23. Rashskin rash1.3%24
  24. Blepharitis1.2%22
  25. Eyelid oedemaa swollen eyelid1.2%22
  26. Skin exfoliationpeeling skin1.2%22

Top 30 of 182 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 12 drugs in the carbonic anhydrase inhibitor class; it describes the reports, not the patients. 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."

Outcomes recorded

Death16%300
Life-threatening0.1%1
Hospitalisation (initial or prolonged)1.5%28
Disability0.4%8
Congenital anomaly0.1%1
Other serious2.9%55
Not serious80.3%1,510

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 19,384 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 20%0
2 to 110%0
12 to 170%0
18 to 440.5%9
45 to 643%56
65 to 747.3%137
75 and over17.5%329
Age not given71.8%1,349

Patient sex

Female65.5%1,231
Male30.4%572
Not given4.1%77

Who reported

Physician3.2%60
Pharmacist3.8%72
Other health professional8.7%163
Lawyer0.1%1
Consumer or non-health professional45.3%852
Not given38.9%732

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 76.3% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Glaucoma1176.2%
Intraocular pressure increased150.8%
Ocular discomfort40.2%
Open angle glaucoma20.1%

The indication field is filled in by the reporter and is often blank; shares are of all 1,880 reports.

Drugs most often listed in the same reports

Drug (any role in the report)ReportsShare of Cosopt Pf reports
Zioptan643.4%
Restasis100.5%
Levothyroxine90.5%
Simvastatin80.4%
Aspirin70.4%
Lumigan70.4%
Metformin70.4%
Januvia60.3%
Lantus60.3%
Lipitor60.3%

Other products listed in reports where Cosopt Pf is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.

In context

MeasureCosopt PfCarbonic anhydrase inhibitorAll reports
Reports as suspect product1,88019,38420,646,523
Share of that pool—9.7%0%
Reports, latest 12 months12—1,332,454
Marked serious19.7%40.1%57.4%
Death recorded among outcomes, per 1,000 reports1604991
Hospitalisation recorded, per 1,000 reports15115213
Consumer-filed share45.3%52.8%45.8%
Top term, share of reportsEye irritation 23.7%median 4.7%0.3%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. 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."

Other drugs in the carbonic anhydrase inhibitor class

DrugName typeReportsLatest 12 monthsMarked serious
Azoptbrand3,6564037.5%
Simbrinzabrand2,9536433.9%
Acetazolamidegeneric2,56725987.3%
Dorzolamidegeneric2,0737518.2%
Keveyisbrand1,5594127.2%
Cosoptbrand1,3473066.9%
Brinzolamidegeneric8866673%
Dorzolamide hydrochloridegeneric6927232.2%
Dorzolamide hclgeneric68802.8%
Dorzolamide and Timololbrand562411.4%
Dorzolamide hydrochloride timolol maleategeneric52110325%

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." A brand and its generic are separate rows because reporters name them separately.

Questions about Cosopt Pf reports

How many adverse event reports has FDA received for Cosopt Pf?

1,880 reports list Cosopt Pf as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 12 of them arrived in the latest 12 months. Another 167 list it only as a concomitant medication.

What reactions are recorded in Cosopt Pf reports?

eye irritation (23.7%), ocular hyperaemia (21.9%), eye pruritus (15.4%), death (10.6%) and eye swelling (9.5%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Cosopt Pf was responsible.

How serious are the reports?

19.7% are marked serious by the reporter. Among the outcomes recorded, 16% of reports include death and 1.5% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

consumer or non-health professional (45.3%), not given (38.9%) and other health professional (8.7%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Cosopt Pf rising?

12 reports in the 12 months to June 2026, down 29% from 17 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Cosopt Pf was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Cosopt Pf?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. 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 report counts here when it lists Cosopt Pf as a suspect or interacting product; reports listing it only as a concomitant medication (167) are excluded. 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.