Medically reviewed by A Ras MD. Last updated on May 20, 2022.
What is Neptazane?
Neptazane reduces the activity of a protein in your body called carbonic anhydrase. Blocking this protein can help reduce the amount of fluid in the eye, which decreases pressure inside the eye.
- Neptazane is used to lower pressure inside the eye (intraocular pressure) in people with certain types of glaucoma.
- Neptazane is also used as a diuretic (“water pill”) in people with congestive heart failure, to reduce the build-up of fluid in the body. This build-up is called edema.
- Neptazane is also used to treat certain types of seizures, and to treat or prevent altitude sickness.
- Neptazane may also be used for purposes not listed in this medication guide.
Methazolamide USP, a sulfonamide derivative, is a white or faintly yellow, crystalline powder having a slight odor, soluble in dimethylformamide, slightly soluble in acetone, very slightly soluble in water and in alcohol. The chemical name for methazolamide is: N-[5-(aminosulfonyl)-3-methyl-1,3,4-thiadiazol-2(3H)-ylidene]-acetamide and it has the following structural formula:
Each tablet, for oral administration, contains 25 mg or 50 mg methazolamide USP. In addition, each tablet contains the following inactive ingredients: colloidal silicon dioxide, croscarmellose sodium, dibasic calcium phosphate dihydrate, magnesium stearate, and microcrystalline cellulose.
What is Neptazane used for?
Neptazane is used to treat glaucoma.
Neptazane may be given to you for other reasons. Talk to your doctor.
Mechanism of action
Methazolamide is a potent inhibitor of carbonic anhydrase.
Before taking Neptazane, tell your doctor:
- If you are allergic to Neptazane; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have any of these health problems: Acidic blood problem, kidney disease, liver disease, low potassium levels, low sodium levels, or poor adrenal function.
- If you are taking acetazolamide.
- If you are breast-feeding or plan to breast-feed.
This is not a list of all drugs or health problems that interact with this medicine.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take Neptazane with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take Neptazane?
- Tell all of your health care providers that you take Neptazane. This includes your doctors, nurses, pharmacists, and dentists.
- Avoid driving and doing other tasks or actions that call for you to be alert until you see how Neptazane affects you.
- Have your eye pressure and eyesight checked as you have been told by the doctor.
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take Neptazane.
- This medicine may make you sunburn more easily. Use care if you will be in the sun. Tell your doctor if you sunburn easily while taking Neptazane.
- If you are also taking aspirin, talk with your doctor. Loss of hunger, fast breathing, sluggishness, coma, and death have happened in people taking high doses of aspirin with Neptazane.
- If you are 65 or older, use Neptazane with care. You could have more side effects.
- Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using Neptazane while you are pregnant.
How is Neptazane best taken?
Use Neptazane as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Keep taking Neptazane as you have been told by your doctor or other health care provider, even if you feel well.
- This medicine may cause you to pass urine more often. To keep from having sleep problems, try not to take too close to bedtime.
What do I do if I miss a dose?
- Take a missed dose as soon as you think about it.
- If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
What are the side effects of Neptazane that I need to call my doctor about immediately?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Signs of electrolyte problems like mood changes, confusion, muscle pain or weakness, a heartbeat that does not feel normal, seizures, not hungry, or very bad upset stomach or throwing up.
- Signs of too much acid in the blood (acidosis) like confusion; fast breathing; fast heartbeat; a heartbeat that does not feel normal; very bad stomach pain, upset stomach, or throwing up; feeling very sleepy; shortness of breath; or feeling very tired or weak.
- Change in eyesight.
- Change in hearing.
- Ringing in ears.
- A burning, numbness, or tingling feeling that is not normal.
- Passing urine more often.
- Rarely, very bad effects have happened with sulfa drugs. Sometimes, these have been deadly. These effects have included liver problems, blood problems, and very bad skin reactions (Stevens-Johnson syndrome/toxic epidermal necrolysis). Call your doctor right away if you have a rash; red, swollen, blistered, or peeling skin; red or irritated eyes; sores in your mouth, throat, nose, or eyes; fever, chills, or sore throat; cough that is new or worse; feeling very tired or weak; any bruising or bleeding; or signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
What are some other side effects of Neptazane?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Upset stomach or throwing up.
- Change in taste.
- Not hungry.
- Feeling sleepy.
- Feeling tired or weak.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
If overdose is suspected:
If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
How do I store and/or throw out Neptazane?
- Store at room temperature.
- Store in a dry place. Do not store in a bathroom.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
SRC: NLM .