dorzolamide/timolol vs timolol
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Side-by-side comparison of dorzolamide/timolol and timolol. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.
minor Known Drug Interaction
7.7 CYP2D6 Inhibitors Potentiated systemic beta-blockade (e.g., decreased heart rate, depression) has been reported during combined treatment with CYP2D6 inhibitors (e.g., quinidine, SSRIs) and timolol. There have been no reports of exacerbation of rebound hypertension with ophthalmic timolol maleate.
Cosopt
Timoptic
Cosopt is an eye drop that lowers pressure inside the eye. It combines two medicines to treat glaucoma and high eye pressure.
No summary available.
Cosopt is used to lower high pressure in your eyes. It treats open-angle glaucoma and ocular hypertension. These conditions can damage the optic nerve and cause vision loss. Cosopt is for people who haven't responded well to beta-blocker eye drops alone.
Information not available.
Cosopt has two medicines. Dorzolamide lowers eye pressure by reducing fluid production in the eye. Timolol lowers eye pressure by blocking certain receptors in the eye.
Information not available.
- • Bitter, sour, or unusual taste
- • Eye burning or stinging
- • Redness of the eye
- • Blurred vision
- • Superficial punctate keratitis (small spots on the cornea)
- • Bitter, sour, or unusual taste
- • Eye burning or stinging
- • Redness of the eye
- • Blurred vision
- • Eye itching
- Treatment not working 1,369
- Tiredness 444
- Headache 356
- Pain 321
- Eye pain 292
- Treatment Failure 3,042
- Fatigue 470
- Hypersensitivity 456
- Dizziness 401
- Diarrhoea 396
Cosopt contains timolol, which can cause breathing problems like asthma. If you have asthma or severe lung disease, you should not use Cosopt. Cosopt can also cause heart problems, including heart failure. If you have heart problems, talk to your doctor before using Cosopt. Cosopt contains dorzolamide, a sulfonamide. Rarely, severe reactions to sulfonamides, including fatal reactions, have occurred. If you have a sulfonamide allergy, you should not use Cosopt.
No specific warnings noted.
It is not known if Cosopt will harm an unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is also not known if Cosopt passes into breast milk. Talk to your doctor about the best way to feed your baby if you use Cosopt.
No pregnancy information available.
How to Read This dorzolamide/timolol vs timolol Comparison
dorzolamide/timolol is classified in the CAI / Beta-Blocker Combination (Ophthalmic) drug class, while timolol sits within the Beta-Blocker (Ophthalmic) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.
Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, dorzolamide/timolol has 2,782 submissions while timolol has 4,765. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known minor interaction flagged in FDA labeling, attributed to using two medications that both contain timolol can lead to an overdose, which may slow your heart rate down too much or cause low blood pressure.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.
A table cannot represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for dorzolamide/timolol or timolol.
Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.