Generic Name: methenamine (meth-EN-a-meen)
Brand Name: Examples include Hiprex and Urex
Hiprex is used for:
Preventing urinary tract infections.
Hiprex is a urinary antiseptic. It works by concentrating in the urine as formaldehyde, which kills bacteria in the urine.
Do NOT use Hiprex if:
- you are allergic to any ingredient in Hiprex
- you have kidney problems
- you are taking a sulfonamide (eg, sulfamethizole)
Contact your doctor or health care provider right away if any of these apply to you.
Before using Hiprex:
Some medical conditions may interact with Hiprex. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have diarrhea, a stomach infection, liver or kidney problems, or gout, or you are severely dehydrated
Some MEDICINES MAY INTERACT with Hiprex. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Sulfonamides (eg, sulfamethizole) because they may decrease Hiprex's effectiveness
This may not be a complete list of all interactions that may occur. Ask your health care provider if Hiprex may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use Hiprex:
Use Hiprex as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Take Hiprex by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
- Before you begin using an antacid, check with your doctor or pharmacist.
- If you miss a dose of Hiprex, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use Hiprex.
Important safety information:
- It is important that your urine be acidic while you are taking Hiprex. Check with your doctor to see if you should eat or avoid certain foods to keep your urine acidic.
- Hiprex may interfere with certain lab tests. Be sure your doctor and lab personnel know you are taking Hiprex.
- Lab tests, including urine pH, may be performed while you use Hiprex. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
- PREGNANCY and BREAST-FEEDING: It is not known if Hiprex can cause harm to the fetus. If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Hiprex while you are pregnant. Hiprex is found in breast milk. If you are or will be breast-feeding while you use Hiprex, check with your doctor. Discuss any possible risks to your baby.
Possible side effects of Hiprex:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Nausea; upset stomach.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); blood in the urine.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.Proper storage of Hiprex:
Store Hiprex at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep Hiprex out of the reach of children and away from pets.
- If you have any questions about Hiprex, please talk with your doctor, pharmacist, or other health care provider.
- Hiprex is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take Hiprex or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Hiprex. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Hiprex. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using Hiprex.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.
More about Hiprex (methenamine)
- Side Effects
- During Pregnancy or Breastfeeding
- Dosage Information
- Drug Images
- Drug Interactions
- Support Group
- Pricing & Coupons
- En Español
- 14 Reviews – Add your own review/rating
- Generic Availability
- Drug class: urinary anti-infectives