Miostat, also known by its generic name carbachol, is an eye injection. It's a cholinergic agonist that works to help control the size of your pupil and lower your eye pressure. A healthcare professional will make sure you get the right dosage and inject the medication into your eye during eye surgery. Side effects can include blurred vision and eye pain.
Making the pupils smaller (miosis) during eye surgery to control eye pressure
Miostat (carbachol) is a cholinergic agonist. It works by tightening certain muscles in the eye. This makes the pupil (black middle part of the eye) smaller. The medication also helps lower eye pressure after eye surgery by helping fluid drain from the eye.
Source: DailyMed
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 as soon as possible if any of the following side effects occur:
Rare
Veil or curtain appearing across part of vision
Symptoms of too much medicine being absorbed into the body
Diarrhea, stomach cramps or pain, or vomiting
fainting
flushing or redness of face
frequent urge to urinate
increased sweating
irregular heartbeat
shortness of breath, wheezing, or tightness in chest
unusual tiredness or weakness
watering of mouth
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
Blurred vision or change in near or distance vision
stinging or burning of the eye
Less common
Headache
irritation or redness of eyes
twitching of eyelids
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.
Makes your pupil smaller within 2 to 5 minutes
Might be used with other medications during your eye surgery
Injected into the eye by an eye surgeon
No lower-cost generic available; brand-name medication only
Tell your care team if you have a latex allergy before your eye surgery. The stopper on the vial of Miostat (carbachol) contains natural rubber (latex), which can lead to an allergic reaction if you have a latex allergy.
Avoid driving after your eye procedure. It might be a good idea to have someone help drive you home. Miostat (carbachol) and possibly other medications that are placed into your eye for your procedure can affect your eyesight afterwards. For example, your vision might not be clear after your eye procedure.
Contact your eye specialist if you experience eye pain, eye inflammation, or concerning vision changes after your surgery.
Miostat (carbachol) 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 factors: Heart failure | Asthma | Stomach ulcer | Hyperactive thyroid (hyperthyroidism) | Spasm in the digestive tract | Blockage of the urinary tract | Parkinson's disease
Miostat (carbachol) can cause various problems if you have certain medical conditions. Before any eye surgery, it's important to tell your eye specialist about all of your medical conditions so they can make sure Miostat (carbachol) is safe for you.
The stopper on the vial containing Miostat (carbachol) has latex in it. Make sure to tell your care team before surgery if you have a latex allergy. Get medical help right away if you experience hives, swelling in your face or throat, or trouble breathing.
Miostat (carbachol) is given by trained healthcare professionals in a hospital setting only. The healthcare professional will inject a small amount of medication into the eye during eye surgery.
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. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.
Making the pupils smaller (miosis) during eye surgery to control eye pressure
High pressure in the eye
Glaucoma (open-angle or acute angle-closure)
Prevention of high eye pressure due to laser eye surgery
Shrinking the size of the pupils (miosis)
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Alcon Laboratories, Inc. (2023). Miostat- carbachol solution [package insert]. DailyMed.
Bausch & Lomb Incorporated. (2023). Miochol E- acetylcholine chloride [package insert]. DailyMed.
Kaptı, H. B., et al. (2022). Effect of intracameral carbachol and epinephrine use on choroidal thickness after uncomplicated phacoemulsification. Medical Science Monitor.
MedlinePlus. (2022). Cloudy cornea.
Nam Patton, D., et al. (2024). Chemical insights into topical agents in intraocular pressure management: From glaucoma etiopathology to therapeutic approaches. Pharmaceutics.
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