[Posted 06/30/2011] A National Alert for Serious Medication Errors has been issued by the American Society of Health-System Pharmacists (ASHP) and the Institute for Safe Medication Practices (ISMP), warning that potentially fatal errors may occur with dosing for the antibiotic colistimethate for injection. The use of this drug has been increasing due to its value as a last resort treatment for multi-drug resistant organisms.
Colistimethate is a prodrug, a pre-cursor of a drug that converts to an active drug in the human body as it is metabolized. However, in the U.S., the strength of all FDA-approved colistimethate for injection products is labeled in terms of the base drug, colistin, not the prodrug. The label expresses the strength as 150 mg of colistin base per vial.
Dosing information also is expressed in terms of the colistin base. However, on the Internet and in some journal references, dosing information is based on the prodrug, colistimethate. This has resulted in situations where the prodrug dose is ordered but confused as a colistin dose, which results in doses approximately 2.5 times higher than intended.
In a recent case, a physician mistakenly ordered a dose of colistimethate as the prodrug, but the amount was dispensed as the colistin base. The patient developed complications including acute renal failure and later died.
The alert provides recommendations to prevent misdosing of colistimethate, which include developing dose limits, restricting prescribing to infectious disease specialists, and monitoring the patients’ renal function. Physicians, pharmacists, and nurses are expected to use these recommendations to take immediate action to prevent serious medication errors at their facility.
Alerts are issued by ASHP and ISMP when a significant risk for serious or fatal errors is detected through ISMP’s National Medication Error Reporting Program (MERP). Alerts are distributed to healthcare practitioners and organizations through ISMP, ASHP, and the National Council on Medication Error Reporting and Prevention.
COLISTIMETHATE, COLISTIN, POLYMYXIN E (koe lis ti METH ate, koe LIS tin, pol i MIX in E) is a polymyxin antibiotic. It is used to treat certain kinds of bacterial infections. It will not work for colds, flu, or other viral infections.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
This medicine is for injection into a muscle or infusion into a vein. 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 this medicine. Use exactly as directed. Take your medicine at regular intervals. Do not take your medicine more often than directed. Take all of your medicine as directed even if you think you are better. Do not skip doses or stop your medicine early.
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. While this drug may be prescribed for selected conditions, precautions do apply.
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.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
What may interact with this medicine?
This medicine may interact with the following medications:
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.
What should I watch for while using this medicine?
Tell your doctor or healthcare professional if your symptoms do not start to get better or if they get worse.
Tell your doctor or health care professional if you have any problems passing urine.
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 treat diarrhea with over the counter products. Contact your doctor if you have diarrhea that lasts more than 2 days or if it is severe and watery.
What side effects may I notice from receiving this medicine?
Side effects that you should report to your doctor or health care professional as soon as possible:
trouble passing urine or change in the amount or color of urine
white patches or sores in the mouth
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
diarrhea
pain at site where injected
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.
Where should I keep my medicine?
Keep out of the reach of children.
If you are using this medicine at home, you will be instructed on how to store this medicine. Throw away any unused medicine after the expiration date on the label.
NOTE:This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
Remember, keep this and all other medicines out of the reach of children,
never share your medicines with others, and use this medication only for the indication prescribed.
