Methazolamide vs. Acetazolamide for Glaucoma: Important Differences and Potential Risks.

Methazolamide

Acetazolamide

Summary for Methazolamide

Prescription only

Methazolamide is used to help lower eye pressure and treats eye conditions like glaucoma in adults. It belongs to the drug class called carbonic anhydrase inhibitors. Methazolamide is a tablet that's taken by mouth, and the dosage is taken 2 or 3 times a day. This medication has many potential side effects, including tingling in the arms or legs, ringing in the ears, and stomach upset. There are possible interactions with aspirin and steroids.

Indications for Methazolamide

High pressure in the eye, such as with glaucoma

Pros and Cons for Methazolamide

Pros

Works well to lower pressure in the eyes
A tablet that's taken by mouth, which might be an option for people who don't like to use eye drops
Available as a lower-cost generic

Cons

Need to take multiple times a day
Many potential side effects, so not typically a first-choice option
Unknown if safe or works well in children

Common Side Effects for Methazolamide

Tingling or "pins and needles" feeling in the arms or legs
Ringing in the ears
Weakness
Tiredness
Loss of appetite
Taste changes
Nausea
Vomiting
Diarrhea
More urination
Vision changes

Warnings for Methazolamide

Severe allergic reactions
Interaction with aspirin
Use with caution in people with breathing or lung problems

Summary for Acetazolamide

Prescription only

Acetazolamide is used to treat altitude sickness (mountain sickness). It can also help with glaucoma, edema (swelling), and epilepsy (a seizure condition). Acetazolamide can have side effects such as tiredness, stomach upset, and sometimes numbness and tingling of the face, arms, or legs. This medication comes as a generic immediate-release (IR) tablet and extended-release (ER) capsule; the brand-name Diamox is no longer available.

Indications for Acetazolamide

Altitude sickness (mountain sickness)
Glaucoma
Edema (swelling in the body due to fluid buildup) - IR tablet only
Epilepsy (petit mal, unlocalized seizures) - IR tablet only

Pros and Cons for Acetazolamide

Pros

Recommended preventative medication for altitude sickness if you're at moderate-to-high risk of developing this condition
Generally a well-tolerated medication
Can use in older people (at lower doses)
Available as a lower-cost generic

Cons

Need to take multiple times a day
Might not be a good option if you have a sulfonamide ("sulfa") allergy
Not recommended for people with serious kidney or liver problems
Not known if it's safe or works well in children (those of all ages for immediate-release and those younger than 12 for extended-release)