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METHYLNALTREXONE (METH il nal TREX one) is used to treat constipation caused by opioids (pain medicine). Immediately tell your health care professional if you stop taking your opioid pain medicine.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
They need to know if you have any of these conditions:
stomach or intestinal blockage or other stomach problems
an unusual or allergic reaction to methylnaltrexone, other medicines, foods, dyes, or preservatives
pregnant or trying to get pregnant
This medicine is for injection under the skin. It is usually given by a health care professional in a hospital or clinic setting. If you get this medicine at home, you will be taught how to prepare and give it. Use exactly as directed. Do not take your medicine more often than directed.
It is important that you put your used needles and syringes in a special sharps container. Do not put them in a trash can. If you do not have a sharps container, call your pharmacist or healthcare provider to get one.
Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
This does not apply; this medicine is not for regular use.
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
Be close to a bathroom after you get this medicine. You may need to use the toilet soon after getting this medicine.
Tell your doctor or healthcare professional if your symptoms do not start to get better or if they get worse.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.
Your condition will be monitored carefully while you are receiving this medicine.
Side effects that you should report to your doctor or health care professional as soon as possible:
severe or persistent diarrhea
severe or persistent stomach pain
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Keep out of the reach of children.
Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Do not freeze and protect from light. Throw away any unused medicine after the expiration date.