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Generic name: methionine [ me-THYE-o-neen ]
Brand name: Me-500

Me-500 is used for:

Acidifying urine. It may also be used for other conditions as determined by your doctor.

Me-500 is an amino acid. It works by neutralizing the ammonia in urine.

Do NOT use Me-500 if:

  • you are allergic to any ingredient in Me-500
  • you have severe liver disease

Contact your doctor or health care provider right away if any of these apply to you.

Before using Me-500:

Some medical conditions may interact with Me-500. 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 high acid levels in the body tissues or liver problems

Some MEDICINES MAY INTERACT with Me-500. However, no specific interactions with Me-500 are known at this time.

This may not be a complete list of all interactions that may occur. Ask your health care provider if Me-500 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 Me-500:

Use Me-500 as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take Me-500 with or following a meal.
  • If you have difficulty swallowing the capsules, they may be dissolved in juice, water, or warm milk.
  • If you miss a dose of Me-500, 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 Me-500.

Important safety information:

  • Me-500 may cause drowsiness. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to Me-500. Using Me-500 alone, with certain other medicines, or with alcohol may lessen your ability to drive or perform other potentially dangerous tasks.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant while taking Me-500, discuss with your doctor the benefits and risks of using Me-500 during pregnancy. It is unknown if Me-500 is excreted in breast milk. If you are or will be breast-feeding while you are using Me-500, check with your doctor or pharmacist to discuss the risks to your baby.

Possible side effects of Me-500:

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:

Drowsiness; nausea; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue).

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 Me-500:

Store Me-500 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 Me-500 out of the reach of children and away from pets.

General information:

  • If you have any questions about Me-500, please talk with your doctor, pharmacist, or other health care provider.
  • Me-500 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 Me-500 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 Me-500. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Me-500. 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 Me-500.

Issue Date: June 3, 2015

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.