
timolol
Istalol (timolol) is an eye drop that's used to lower pressure within the eye and treat glaucoma. It belongs to the beta blocker drug class. This medication can be used by itself or together with other eye drops that aren't beta blockers. Istalol (timolol) is longer-acting than other timolol products, so the usual dosage is once daily in the morning. Common side effects include burning or stinging after you put in the eye drops, but it's generally a temporary feeling.
What is Istalol (timolol)?
What is Istalol (timolol) 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)
How Istalol (timolol) works
Istalol (timolol) is a beta blocker that lowers the amount of fluid in the eye. When there's less fluid inside the eye, the eye pressure goes down.
Drug facts
| Common Brands | Istalol |
|---|---|
| Drug Class | Beta blocker |
| Controlled Substance Classification | Not a controlled medication |
| Generic Status | Lower-cost generic available |
| Availability | Prescription only |
More on Istalol (timolol) essentials
Side effects of Istalol (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
- Temporary burning or stinging in the eye after using (38%)
Less Common Side Effects
- Blurred vision
- Cataract
- Eye infection
- Itchy eye
- Vision not as sharp
- Headache
- High blood pressure
Istalol (timolol) serious side effects
Contact your healthcare provider immediately if you experience any of the following.
- Trouble breathing: shortness of breath, wheezing, chest tightness
- Heart failure: shortness of breath; fatigue; swelling in the legs, ankles and feet
- Allergic reactions: rash around your eyes or face, closing of the throat, hives, swelling
More on Istalol (timolol) side effects
The following Istalol (timolol) 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
Chest pain or discomfort
lightheadedness, dizziness, or fainting
shortness of breath
slow or irregular heartbeat
unusual tiredness
Rare
Noisy breathing
small clicking, bubbling, or rattling sounds in the lung when listening with a stethoscope
swelling of hands, ankles, feet, or lower legs
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
Blurred vision
continuing ringing or buzzing or other unexplained noise in ears
headache
hearing loss
nervousness
pounding in the ears
sweating
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:
Rare
Acid or sour stomach
belching
burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
decreased interest in sexual intercourse
feeling of constant movement of self or surroundings
inability to have or keep an erection
indigestion
lack or loss of strength
loss in sexual ability, desire, drive, or performance
sensation of spinning
stomach discomfort, upset, or pain
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.
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Pros and cons of Istalol (timolol)
Pros
- Works well to treat high eye pressure
- Used only once daily
- Lower-cost generic available
Cons
- Unknown if safe for use in children
- Might cause more side effects than some other timolol eye medications
Pharmacist tips for Istalol (timolol)
- Wash your hands before placing Istalol (timolol) drops in your eyes. Avoid touching the dropper tip to your eye or any other surface. Don't touch the dropper tip with your hands. This helps prevent the eye drop solution from getting contaminated with germs and lower the risk for eye infections.
- If you wear contact lenses, remove them before you place Istalol (timolol) into your eye(s). Wait 15 minutes before putting your lenses back in your eye(s).
- After placing a drop of Istalol (timolol) in your eye, close your eye and gently press one finger to the inner corner of your eye by the nose for 1 minute. This helps your eye absorb the medication.
- If you need to use Istalol (timolol) along with other eye drops or ointments, wait 5 minutes between using each product to give your eyes time to absorb each medication.
- It's not easy to tell whether your eye pressure is improving at home. Use Istalol (timolol) as prescribed, even if you don't notice any differences in your symptoms or vision right away.
Risks and warnings for Istalol (timolol)
Istalol (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.
Higher risk for heart failure
- Risk factors: Congestive heart failure | Second- or third-degree heart block
In rare cases, some people developed heart failure while they used beta-blocking medications like Istalol (timolol). People who already have heart failure might be at risk for worsening heart problems with this medication. Tell your healthcare team about your medical history. And talk to your primary care provider if you notice swelling in your feet or ankles, a fast or irregular pulse, or shortness of breath when you lie down or exercise. These might be signs of heart problems.
Not recommended for people with breathing problems
- Risk factors: History of asthma | History of chronic obstructive pulmonary disease (COPD) | History of other lung problems
Beta blocker medications like Istalol (timolol) usually aren't recommended for people with lung problems, like asthma and COPD. This is because beta blockers can cause the airways to become narrower, which can make it harder to breathe. But the risk for breathing problems specifically with Istalol (timolol) isn't well known. Make sure your healthcare team knows if you have or have ever had any lung problems or conditions before you start using this medication to check whether it's safe for you.
Hidden symptoms of low blood sugar
- Risk factors: Diabetes
Beta blockers can cause people with diabetes to not notice symptoms of low blood sugar, except for sweating and dizziness. It's possible for some Istalol (timolol) to be absorbed into your bloodstream and cause this effect. So though rare, it's important to be aware of this risk. Talk to your primary care provider to see whether you should check your blood sugar more often if you're using Istalol (timolol).
Hidden symptoms of overactive thyroid
Beta blockers can cause people with an overactive thyroid to not recognize the signs of hyperthyroidism, such as a fast heart rate. It's possible for some Istalol (timolol) to get absorbed into your bloodstream and cause this effect. Although rare, it's good to be aware of this risk. Make sure your primary care provider knows that you're using Istalol (timolol) so they can monitor your thyroid problem more closely.
Worsening of myasthenia gravis
In some rare cases, Istalol (timolol) can worsen symptoms like muscle weakness in people who have myasthenia gravis. Watch out for worsening symptoms if you have myasthenia gravis and let your care team know if this happens to you.
Istalol (timolol) dosage
| Dosage | Quantity | Price as low as | Price per unit |
|---|---|---|---|
| 5ml of 0.5% | 1 eye dropper | $9.50 | $9.50 |
| 2.5ml of 0.5% | 1 eye dropper | $41.05 | $41.05 |
Typical dosage for Istalol (timolol)
The typical dose is 1 drop in the affected eye(s) once daily in the morning.
Interactions between Istalol (timolol) and other drugs
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
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.
- Albuterol
- Ceritinib
- Crizotinib
- Dronedarone
- Fenoldopam
- Fingolimod
- Formoterol
- Indacaterol
- Iobenguane I 131
- Iohexol
- Lacosamide
- Levalbuterol
- Olodaterol
- Oxymetazoline
- Paroxetine
- Ponesimod
- Rivastigmine
- Salmeterol
- Terbutaline
- Vilanterol
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.
- Aceclofenac
- Acemetacin
- Amtolmetin Guacil
- Aspirin
- Bromfenac
- Bufexamac
- Celecoxib
- Choline Salicylate
- Clonixin
- Dexibuprofen
- Dexketoprofen
- Diclofenac
- Diflunisal
- Dipyrone
- Droxicam
- Etodolac
- Etofenamate
- Etoricoxib
- Felbinac
- Fenoprofen
- Fepradinol
- Feprazone
- Floctafenine
- Flufenamic Acid
- Flurbiprofen
- Ibuprofen
- Indomethacin
- Ketoprofen
- Ketorolac
- Lornoxicam
- Loxoprofen
- Lumiracoxib
- Meclofenamate
- Mefenamic Acid
- Meloxicam
- Morniflumate
- Nabumetone
- Naproxen
- Nepafenac
- Niflumic Acid
- Nimesulide
- Nimesulide Beta Cyclodextrin
- Oxaprozin
- Oxyphenbutazone
- Parecoxib
- Phenylbutazone
- Piketoprofen
- Piroxicam
- Pranoprofen
- Proglumetacin
- Propyphenazone
- Proquazone
- Rofecoxib
- Salicylic Acid
- Salsalate
- Sodium Salicylate
- St John's Wort
- Sulindac
- Tenoxicam
- Tiaprofenic Acid
- Tolfenamic Acid
- Tolmetin
- Valdecoxib
How much does Istalol (timolol) cost?
Istalol (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 Istalol (timolol) will not be safe for you to take.
- Asthma
- Chronic obstructive pulmonary disease (COPD)
- Sinus bradycardia (slow heart rate)
- Second- or third-degree heart block
- Heart failure
- Cardiogenic shock
What are alternatives to Istalol (timolol)?
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