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Dorzolamide / Timolol Coupon - Dorzolamide / Timolol 10ml of 2%/0.5% eye dropper

dorzolamide / timolol

Generic Cosopt
Used for Glaucoma, Eye Pressure
Used for Glaucoma, Eye Pressure

Cosopt is a combination ophthalmic drop (eye drop) medication that contains dorzolamide (a carbonic anhydrase inhibitor) and timolol (a beta blocker). It's used to lower eye pressure for certain people with glaucoma or high eye pressure. Typically, one drop of Cosopt (dorzolamide / timolol) is placed into the affected eye(s) twice a day. Common side effects of this medication include changes in taste, blurry vision, and itchy eyes. Cosopt (dorzolamide / timolol) is available as both brand name and generic medications. It comes in a multi-dose bottle, as well as single-use, preservative-free vials.

Reviewed by:
reviewer
Ally Tsai, PharmD
reviewer
Kristianne Hannemann, PharmD
Last reviewed on April 22, 2024
BasicsSide effectsPros & consPharmacist tipsFAQsWarningsDosageInteractionsCostContraindicationsAlternativesLatest newsImagesReferencesPricesMedicare
basics-icon

What is Cosopt (dorzolamide / timolol)?

What is Cosopt (dorzolamide / timolol) used for?

How Cosopt (dorzolamide / timolol) works

Cosopt (dorzolamide / timolol) is a combination of two medications that work together to lower eye pressure:

Are you looking for information on dorzolamide (Trusopt) or timolol (Timoptic) eye drops instead?
When does Cosopt (dorzolamide / timolol) start working?
Time passed since treatment started:
HOURS
DAYS
WEEKS
MONTHS
Full effect

Drug Facts

Common BrandsCosopt, Cosopt PF
Drug ClassCarbonic anhydrase inhibitor / Beta blocker
Controlled Substance ClassificationNot a controlled medication
Generic StatusLower-cost generic available
AvailabilityPrescription only
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Avg retail price
$61.830
GoodRx discount
$61.83
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What are the side effects of Cosopt (dorzolamide / timolol)?

The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

Common Side Effects

  • Changes in taste (up to 30%)
  • Eye burning or stinging (up to 30%)
  • Blurry vision (5-15%)
  • Itchy eye (5-15%)
  • Corneal inflammation (5-15%)
  • Eye redness (5-15%)

Other Side Effects

  • Belly pain
  • Bronchitis
  • Cloudy vision
  • Eye discharge or swelling
  • Eyelid swelling
  • Dizziness
  • Dry eyes
  • Eye tearing
  • Headache
  • Sinus infection
  • Upper respiratory infection

Serious Side Effects

Contact your healthcare provider immediately if you experience any of the following.
  • Worsening heart failure: shortness of breath, unusual swelling, tiredness, sudden weight gain
  • Bronchospasm: tightness in the chest, trouble catching your breath, difficulty breathing, wheezing, cough, dizziness, extreme tiredness
  • Serious allergic and skin reactions: hives, rash, blisters, swelling of the lips or tongue, difficulty breathing, skin reddening
When do Cosopt (dorzolamide / timolol) possible side effects begin and end?
Time passed since treatment started:
MINUTES
HOURS
DAYS
WEEKS
MONTHS
Eye discomfort
Bitter taste in mouth

Source: DailyMed

The following side effects have also been reported

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

Blurred vision

burning or stinging of the eye (when medicine is applied)

feeling of something in the eye

itching of the eye

redness of the eye and lining of the eyelid

sensitivity of the eyes to light

Less common

Back, abdominal, or stomach pain

change in vision

coughing, shortness of breath, troubled breathing, tightness in the chest, or wheezing

discharge from the eye

dizziness

eye or eyelid pain, swelling, discomfort, or irritation

increased blood pressure

increased frequency of urination or painful urination

itching of the eyelid

seeing flashes or sparks of light

seeing floating spots before the eyes

swelling of lining of the eyelid

tiny bumps on lining of the eyelid

Rare

Blistering, peeling, or loosening of the skin

blood in the urine

blue lips, fingernails, or skin

chest pain or discomfort

chills

cough

diarrhea

difficult or troubled breathing

fainting

headache or weakness, severe and sudden

irregular, fast or slow, or shallow breathing

itching

joint or muscle pain

lightheadedness

mental depression

nausea or vomiting

pain, numbness, tingling, or burning feeling in the hands or feet

red, irritated eyes

red skin lesions, often with a purple center

shortness of breath

skin rash

slow or irregular heartbeat

sore throat

sores, ulcers, or white spots in the mouth or on the lips

sweating

unusual tiredness or weakness

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose

Confusion

muscle cramps or pain

numbness, tingling, pain, or weakness in the hands or feet

seizures

trembling

weakness and heaviness of the legs

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Bitter, sour, or unusual taste

Less common

Cold- or flu-like symptoms

crusting or scales on eyelid

dryness of the eyes

indigestion or upset stomach

sore throat

stuffy or runny nose

tearing of the eye

Rare

Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings

depression

dry mouth

stuffy nose

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

pros-and-cons

Pros and cons of Cosopt (dorzolamide / timolol)

thumbs-up

Pros

Available in a preservative-free form if you're sensitive to the preservative, benzalkonium chloride

Available as a lower-cost generic medication

Combines two medications into one eye drop for convenience

thumbs-down

Cons

Might not be safe if you're allergic to sulfa medications

Not safe for use in uncontrolled asthma or chronic obstructive pulmonary disease (COPD)

Needs to be used twice a day

pharmacist-tips

Pharmacist tips for Cosopt (dorzolamide / timolol)

pharmacist

  • If you wear contact lenses, make sure to take them out before using Cosopt (dorzolamide / timolol). Wearing contact lenses while using Cosopt (dorzolamide / timolol) can cause the medication to work less well. If you use a multidose bottle, your contact lenses can absorb the preservative, which can further irritate your eyes. Make sure to wait at least 15 minutes after using the medication to put them back in.

    • To use Cosopt (dorzolamide / timolol), pull down your lower eyelid with one hand and hold the bottle upside down with the other. Make sure the tip of the bottle is above your eye, but don't let the tip touch your eye. Squeeze 1 drop of medication into your eye. Then, close your eye, and press your finger on the corner of your eye closest to your nose for a minute. Doing this helps the medication stay in your eye and prevents it from leaking into your nose.

      • If you need to use another eye drop medication in the same eye, wait at least 5 minutes after using Cosopt (dorzolamide / timolol) so the second eye drop doesn't rinse off the first one.

        • Cosopt (dorzolamide / timolol) contains dorzolamide, a sulfa medication. Be sure to tell your eye specialist if you've an allergy to sulfa-containing medications. You might need to use different eye drops.

          • Let your eye specialist know if you're pregnant before using Cosopt (dorzolamide / timolol). If you're pregnant or thinking of getting pregnant during treatment, contact your eye specialist.

            • If you have diabetes, be careful using Cosopt (dorzolamide / timolol), since this medication can hide symptoms of low blood sugar, except for sweating and dizziness.

              • Let your eye specialist know about your medical history before starting this medication. Timolol in Cosopt (dorzolamide / timolol) can cause your muscle weakness to worsen if you've a history of myasthenia gravis or muscle disorders. Dorzolamide in Cosopt (dorzolamide / timolol) also hasn't been studied in people with severe kidney or liver problems.

                • It's not easy to tell if your eye pressure has improved at home. Make sure to use Cosopt (dorzolamide / timolol) regularly as prescribed by your eye specialist, even if you don't notice any difference in your vision right away.

                  More tips on using preservative-free Cosopt (dorzolamide / timolol)

                  • For preservative-free vials, write down the date you open the foil pouch on the outside of the pouch. Remember to throw away any unused Cosopt (dorzolamide / timolol) vials inside the foil pouch 15 days after opening it.

                    • Keep preservative-free vials in the original foil pouch at room temperature. Protect the medication from light.

                      • Don't open a preservative-free vial until you're ready to use Cosopt (dorzolamide / timolol). After you've placed a drop in the affected eye(s), throw the vial away. Don't save any leftover medication. These single-use vials don't have any preservatives in them to prevent germs from growing in the medication. So, opening the vial before you're ready to use it and using any leftover medication can raise your risk of an eye infection.

                        faqs

                        Frequently asked questions about Cosopt (dorzolamide / timolol)

                        How long can you use Cosopt (dorzolamide / timolol)?
                        Your eye specialist will let you know how long you need to use Cosopt (dorzolamide / timolol). Typically, this depends on how well Cosopt (dorzolamide / timolol) works to lower your eye pressure and whether you're experiencing any serious side effects. In most eye conditions, such as glaucoma), your eye specialist might ask you to use this medication every day to keep your eye pressure under control. But let your care team know right away if you experience side effects, such as eye pain or swelling. Depending on your symptoms, they might ask you to stop Cosopt (dorzolamide / timolol).
                        How long does Cosopt (dorzolamide / timolol) take to work?
                        When you start Cosopt (dorzolamide / timolol), your eye specialist will check your eye pressure regularly to see whether this medication is working for you. One study showed that people who used the eye drops consistently had lower eye pressure at the 6-week check point. Keep in mind that Cosopt (dorzolamide / timolol) works best when it's used regularly in the affected eye(s) two times daily. Missing a dose or using this medication not as directed can cause Cosopt (dorzolamide / timolol) to not work as well. Your eye specialist will let you know how often you should come in for eye exams.
                        Does Cosopt (dorzolamide / timolol) lower blood pressure?
                        Though rare, few people have reported lower blood pressure after starting Cosopt (dorzolamide / timolol). But it's unclear whether the low blood pressure was caused by Cosopt (dorzolamide / timolol) or by other factors. Cosopt contains timolol, a beta blocker. Typically, beta blockers can lower blood pressure. But because Cosopt (dorzolamide / timolol) drops are placed in the eyes, it might not have as noticeable of an effect on blood pressure compared to timolol that's taken by mouth. Talk with your eye specialist if you're concerned about how Cosopt (dorzolamide / timolol) might affect blood pressure.
                        Does Cosopt (dorzolamide / timolol) need to be refrigerated?
                        No, Cosopt (dorzolamide / timolol) doesn't need to be refrigerated. You can store this medication at room temperature in the original container or pouch. Make sure to protect Cosopt (dorzolamide / timolol) from light, since long exposure to heat and light can cause it to not work as well.
                        How long is Cosopt (dorzolamide / timolol) good for after opening?
                        An opened multi-dose bottle of Cosopt (dorzolamide / timolol) can be used until the expiration date on the bottle. Each Cosopt (dorzolamide / timolol) preservative-free vial should only be used once and thrown away. This is because the vials don't have preservatives, which have a higher risk of contamination. Once a pouch of preservative-free vials is opened, store the remaining vials in the foil pouch and throw them away after 15 days.
                        Is Cosopt (dorzolamide / timolol) preservative-free?
                        Cosopt (dorzolamide / timolol) is available in both preservative-free and multi-dose formulations. Preservative ingredients in eye drop medications can sometimes cause serious eye irritation, especially if you use them for a long time. If you're sensitive to preservatives, such as benzalkonium chloride, the preservative-free formulation might be less likely to cause eye discomfort. Speak to your eye specialist if preservative-free formulation best fits your needs.
                        Is Cosopt the same as Combigan?
                        Cosopt (dorzolamide / timolol) and Combigan (brimonidine / timolol) are both eye drop medications to treat high eye pressure in certain people with glaucoma, but they aren't the same. While both eye drops contain timolol, Cosopt also contains dorzolamide (a carbonic anhydrase inhibitor) and Combigan contains brimonidine (an alpha agonist). Cosopt is available in both preservative-free vials (each vial can be used once) and multi-dose bottles (each bottle can be used multiple times). Combigan is only available in multi-dose bottles. Both medications are available by prescription from your eye specialist and have lower-cost generics. Talk with your eye specialist if you've more questions about Cosopt and Combigan.
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                        warings-icon

                        What are the risks and warnings for Cosopt (dorzolamide / timolol)?

                        Cosopt (dorzolamide / timolol) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.

                        risk-warning

                        Risk of difficulty breathing

                        • Risk factors: Chronic obstructive pulmonary disease (COPD) | Asthma

                          Cosopt (dorzolamide / timolol) contains timolol, which can rarely cause the vessels in your lung to tighten. This can make breathing difficult, especially in people with breathing problems, like asthma. This problem is very rare with Cosopt (dorzolamide / timolol) because it's used in your eyes and it's not absorbed into your blood in a large amount. To be safe, make sure your eye specialist knows about your full medical history before starting this medication. Your eye specialist will start you on the lowest dose possible that works well for you.

                          risk-warning

                          Heart failure

                          • Risk factors: Heart failure | Sudden heart attack

                            Taking beta blockers might lead to heart failure or worsen heart failure in people who already have it. This is because beta blockers can slow down your heart, which leads to your heart muscle not pumping as often.

                            Cosopt contains timolol, a beta blocker. It's unclear whether using a beta blocker eye drop carries the same risk of heart failure as taking an oral beta blocker. But there's a chance that people with heart failure might not be able to use Cosopt (dorzolamide / timolol) if their symptoms aren’t well-managed. Discuss with your eye specialist before starting Cosopt (dorzolamide / timolol) if you've a history of heart failure. Let your eye specialist know right away if you experience symptoms such as trouble breathing, tiredness, swelling in your body, or sudden weight gain. They might ask you to stop this medication

                            risk-warning

                            Severe allergic and skin reactions

                            • Risk factor: Allergy to sulfa medications

                              Severe allergic reactions to Cosopt (dorzolamide / timolol) are possible, including life-threatening reactions, like facial swelling and anaphylaxis. Let your eye specialist know if you have a sulfa allergy. If you notice hives, rash, swelling of the lips or tongue, or difficulty breathing after using Cosopt (dorzolamide / timolol), get medical attention right away.

                              Although rare, Cosopt (dorzolamide / timolol) can also cause serious skin reactions, such as Stevens-Johnson syndrome (SJS) and Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS syndrome). If you notice changes in your skin, such as rash, blisters, skin reddening, or skin peeling, stop using Cosopt (dorzolamide / timolol) and get medical attention right away.

                              risk-warning

                              Hiding symptoms of low blood sugar

                              • Risk factors: Diabetes | History of high blood sugar

                                Taking oral beta blockers can make it difficult for you to identify some symptoms of low blood sugar, such as fast heartbeat or tremors. This means you might not be able to rely on all the typical symptoms of low blood sugar to warn you of a dangerous drop in your sugar levels. Sweating might be the only symptom not affected by taking Cosopt (dorzolamide / timolol).

                                Cosopt contains timolol, a beta blocker. But it's unclear whether timolol in eye drops will mask low blood sugar symptoms to the same degree as an oral beta blocker. If you've diabetes, speak with your endocrinologist about how often to monitor your blood sugar once you start Cosopt (dorzolamide / timolol).

                                risk-warning

                                Hiding symptoms of overactive thyroid

                                • Risk factor: Hyperthyroidism

                                  If you have hyperthyroidism (overactive thyroid), don't suddenly stop taking Cosopt (dorzolamide / timolol) without first talking to your eye specialist. Doing so might lead to a condition called a "thyroid storm,” which include symptoms such as a high temperature, rapid heartbeat, and fainting. Get medical attention right away if you've these symptoms.

                                  risk-warning

                                  Greater risk during surgery

                                  • Risk factor: Major surgery requiring anesthesia

                                    If you're planning to undergo a major surgery requiring anesthesia, tell your surgeon that you're using Cosopt (dorzolamide / timolol). Beta-blockers, such as timolol in Cosopt (dorzolamide / timolol), might raise the risk of side effects, such as changes in heartbeat or low blood pressure, from anesthesia. If you've been using it for a while, your surgeon might not ask you to stop it, but they'll need to monitor your heart closely during your procedure.

                                    risk-warning

                                    Cornea swelling

                                    • Risk factor: Low number of cells on the cornea

                                      Cosopt (dorzolamide / timolol) contains dorzolamide, which raises the risk of cornea (the protective covering on the front of the eye) swelling. If you've ever been told that your cornea is thin or has a low number of cells, you might be at risk for this side effect. Talk to your eye specialist before starting Cosopt (dorzolamide / timolol).

                                      risk-warning

                                      Eye inflammation and infection

                                      • Risk factors: Eye inflammation | Using a multiple-dose bottle | Eye infection

                                        Cosopt (dorzolamide / timolol) might cause or worsen inflammation of the eyes. Your risk of eye inflammation and infection is higher if you're using multiple-dose eye drops or have had an eye infection during treatment with this medication. Let your eye specialist know if you have symptoms of red, itchy, or painful eyes. Ask them if you should continue to use Cosopt (dorzolamide / timolol) while your eyes are inflamed. Consider using the preservative-free version of Cosopt (dorzolamide / timolol) if you've frequent eye infection.

                                        risk-warning

                                        Risk of muscle weakness

                                        Though extremely rare, some people using Cosopt (dorzolamide / timolol) have reported muscle weakness in or around the eyes that have led to droopy eyelids or double vision. Let your eye specialist know right away if you experience these symptoms.

                                        dosage

                                        Cosopt (dorzolamide / timolol) dosage forms

                                        The average cost for 1 eye dropper of 10ml of 2%/0.5% of Cosopt (dorzolamide / timolol) is $229.87 with a free GoodRx coupon. This is 19.15% off the average retail price of $284.32.
                                        eye dropper
                                        Eye dropper
                                        DosageQuantityPrice as low asPrice per unit
                                        10ml of 2%/0.5%1 eye dropper$229.87$229.87

                                        Typical dosing for Cosopt (dorzolamide / timolol)

                                        Cosopt, Cosopt PF, and generic eye drops all contain 2% of dorzolamide and 0.5% of timolol.

                                        • Adults and children age 2 and older: The typical dose is to place 1 drop in the affected eye(s) twice a day.

                                        interactions

                                        Interactions between Cosopt (dorzolamide / timolol) and other drugs

                                        Cosopt (dorzolamide / timolol) may interact with certain medications or supplements. Always let your doctor and pharmacist know about any other medications or supplements (including prescribed and over-the-counter medications, vitamins, and dietary or herbal supplements) that you are currently taking. The list below does not include all possible drug interactions with Cosopt (dorzolamide / timolol). Please note that only the generic name of each medication is listed below.

                                        Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

                                        Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

                                        drug-cost

                                        How much does Cosopt (dorzolamide / timolol) cost?

                                        To access savings, use a GoodRx coupon and pay just a fraction of the retail price.
                                        Cosopt (brand)
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                                        $229.87

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                                        Cosopt (dorzolamide / timolol) (generic)
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                                        $61.83

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                                        contraindications-icon

                                        Cosopt (dorzolamide / timolol) contraindications

                                        Contraindications are specific health conditions or situations in which a person should not take a medication due to safety concerns. If you have any of the following conditions or if any of the following apply to you, let your healthcare provider know because Cosopt (dorzolamide / timolol) will not be safe for you to take.

                                        • Asthma

                                        • Chronic obstructive pulmonary disease (COPD)

                                        • Symptomatic heart failure

                                        • Second or third degree heart block

                                        • Slow heartbeat

                                        • Heart not pumping enough blood

                                        alternatives

                                        What are alternatives to Cosopt (dorzolamide / timolol)?

                                        There are a number of medications that your doctor can prescribe in place of Cosopt (dorzolamide / timolol). Compare a few possible alternatives below.
                                        Cosopt (dorzolamide / timolol)
                                        Used for:
                                        $61.83 Lowest GoodRx priceView Prices
                                        Latanoprost (Xalatan)
                                        Used for:

                                        • High pressure in the eye caused by ocular hypertension (high pressure inside the eye) or open-angle glaucoma (the most common type of glaucoma)

                                        $8.99 Lowest GoodRx priceView Prices
                                        Combigan (brimonidine / timolol)
                                        Used for:
                                        $33.34 Lowest GoodRx priceView Prices
                                        images

                                        Cosopt (dorzolamide / timolol) images

                                        This medicine is Colorless Eye Dropper.
                                        This medicine is Colorless Eye Dropper.
                                        colorless - Dorzolamide Hydrochloride / Timolol Maleate 2%-0.5% Ophthalmic Solution
                                        This medicine is Colorless Eye Dropper.colorless - Dorzolamide Hydrochloride / Timolol Maleate 2%-0.5% Ophthalmic Solution

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                                        References

                                        Best studies we found

                                        American Academy of Ophthalmology. (2022). How long can you use prescription eye drops after opening them?

                                        Aslam, S., et al. (2023). Carbonic anhydrase inhibitors. StatPearls.

                                        Chan, K., et al. (2007). Ocular comfort of combination glaucoma therapies: Brimonidine 0.2%/timolol 0.5% compared with dorzolamide 2%/timolol 0.5%. Journal of Ocular Pharmacology and Therapeutics.

                                        View All References (7)

                                        Crichton, A.C.S., et al. (2010). Effectiveness of dorzolamide–timolol (COSOPT) in patients who were treatment naive for open-angle glaucoma or ocular hypertension: The COSOPT First-Line Study. Journal of Ocular Pharmacology and Therapeutics.

                                        National Eye Institute. (2021). Glaucoma medicines.

                                        National Eye Institute. (2021). How to put in eye drops.

                                        Thea Pharma Inc. (2024). COSOPT PF- dorzolamide hydrochloride and timolol maleate solution/ drops [package insert]. DailyMed.

                                        Thea Pharma Inc. (2023). COSOPT- dorzolamide hydrochloride and timolol maleate solution/ drops [package insert]. DailyMed.

                                        Thygesen, J. (2018). Glaucoma therapy: Preservative-free for all? Clinical Ophthalmology.

                                        Vue, M.H., et al. (2011). Drug-induced glucose alterations part 1: Drug-induced hypoglycemia. Diabetes Spectrum.

                                        GoodRx Health has strict sourcing policies and relies on primary sources such as medical organizations, governmental agencies, academic institutions, and peer-reviewed scientific journals. Learn more about how we ensure our content is accurate, thorough, and unbiased by reading our editorial guidelines.
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