Colistimethate is an antibiotic used to treat certain bacterial infections. It works by stopping the growth of bacteria.
OTHER USES: This section contains uses of this drug that are not listed in the approved US professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.
In patients with cystic fibrosis, inhaled colistimethate may be used to treat serious bacterial lung infections (Pseudomonas aeruginosa). See also the Storage section for information about important safety concerns when this medication is inhaled.
Colistimethate for injection is usually given into a vein or a muscle as directed by your doctor. The dosage is based on your medical condition and response to treatment.
If you are giving this medication to yourself at home, learn all preparation and usage instructions from your health care professional. Before using, check this product visually for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely.
If you are inhaling this medication, learn how to prepare the solution and use the nebulizer machine properly. See also the Storage section. If you have any questions, ask your health care professional.
Antibiotics work best when the amount of medicine in your body is kept at a constant level. Therefore, use this drug at evenly spaced intervals.
Continue to use this medication until the full prescribed amount is finished, even if symptoms disappear after a few days. Stopping the medication too early may result in a return of the infection.
Tell your doctor if your condition does not improve or if it worsens.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor right away if you have any serious side effects, including: numbness/tingling (especially of the arms/legs, around the mouth/tongue), strange feeling on the skin of the arms/legs, mental/mood changes (such as confusion, psychosis, seizures), difficulty walking, unsteadiness, slow/shallow/troubled breathing, dizziness/feeling of spinning, unexplained fever, slurred speech, muscle weakness, change in the amount of urine, red/pink urine.
This medication may rarely cause a severe intestinal condition (Clostridium difficile-associated diarrhea) due to a type of resistant bacteria. This condition may occur during treatment or weeks to months after treatment has stopped. Do not use anti-diarrhea products or narcotic pain medications if you have any of the following symptoms because these products may make them worse. Tell your doctor right away if you develop: persistent diarrhea, abdominal or stomach pain/cramping, blood/mucus in your stool.
Use of this medication for prolonged or repeated periods may result in a new infection. Tell your doctor if you notice any symptoms of a new infection (such as white patches in your mouth, a change in vaginal discharge).
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Before using colistimethate, tell your doctor or pharmacist if you are allergic to it; or to polymyxin B or colistin; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This drug may make you dizzy. Do not drive, use machinery, or do any activity that requires alertness until you are sure you can perform such activities safely. Limit alcoholic beverages.
Before having surgery or any procedure requiring anesthesia or medications that block nerve or muscle activity, tell your doctor or dentist that you are using this medication.
This medication may cause live bacterial vaccines (such as typhoid vaccine) not to work as well. Therefore, do not have any immunizations/vaccinations while using this medication without the consent of your doctor.
Older adults may be more sensitive to the side effects of this drug, especially kidney problems.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug include: cephalothin.
Although most antibiotics probably do not affect hormonal birth control such as pills, patch, or ring, some antibiotics may decrease their effectiveness. This could cause pregnancy. Examples include rifamycins such as rifampin or rifabutin. Be sure to ask your doctor or pharmacist if you should use additional reliable birth control methods while using this antibiotic.
If overdose is suspected, contact a poison control center or emergency room immediately. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: extreme drowsiness, slow/shallow breathing, muscle weakness, inability to move.
Do not share this medication with others.
Laboratory and/or medical tests (such as kidney tests) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
For the best possible benefit, it is important to receive each scheduled dose of this medication as directed. If you miss an injection, contact your doctor or pharmacist immediately to establish a new dosing schedule. Do not double the dose to catch up.
If you miss an inhaled dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.
For colistimethate injection, consult the product instructions and your pharmacist for storage details.
If you are using colistimethate as an inhalation, store the unmixed vials at room temperature. Do not use premixed solution or prepare the solution ahead of time because this increases the risk of very serious breathing problems. Prepare the inhalation solution right before use. Discard any unused solution after 24 hours. Do not store for longer periods. Ask your health care professional for details.
Do not store in the bathroom. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised April 2014. Copyright(c) 2014 First Databank, Inc.
With WebMD's Medicine Cabinet, you can check interactions with drugs.Go to medicine cabinet