Vancomycin

Vancomycin is an antibiotic drug used to treat a number of very serious infections that often are not able to be treated through conventional antibiotic therapies.

Overview:

Vancomycin comes in two different forms. The oral form of the drug is used for only a limited number of conditions. The intravenous form of this drug is used to treat many different types of infections. Vancomycin is usually not the first choice for treating an infection. Normally, this drug is used when there are no other types of antibiotics that are able to treat a specific infection. Often, Vancomycin must be used in combination with other antibiotics to treat certain infections that are particularly resistant to antibiotic therapy. Vancomycin is also used for patients who are allergic to penicillin and penicillin-type drugs. Cephalosporins and erythromycins are normally used first, but these drugs may not be effective for all conditions that penicillin is used to treat.

Vancomycin has long been used by doctors as the last drug available to treat infections that are becoming more and more resistant to conventional antibiotic therapy. Many of the older antibiotics will no longer treat diseases that were highly susceptible to that drug in past years. Vancomycin is reserved by doctors because they want to make sure that there are still drugs available to treat the growing number of resistant diseases.

This drug is especially critical in the treatment of methicillin-resistant staphylococcus aureus also known as MRSA. Currently, this is one of only a handful of drugs that can treat this life-threatening condition.

In the last few years, many bacterial diseases have become resistant to even vancomycin. Even some forms of MRSA are becoming resistant to standard vancomycin treatment. This has led doctors to have to rely on using vancomycin as part of a cocktail of various antibiotics in order to combat a number of bacterial conditions.

Vancomycin is derived from a substance known as Amycolatopsis orientalis. This antibiotic works in two different ways. It disturbs the cellular walls of a bacteria and destroys it. Those bacteria that are not destroyed are unable to reproduce and then die.

This drug is excreted through the kidneys. Those with reduced kidney function will have greater difficulty eliminating the drug from their systems. Over 75% of the drug is eliminated from the body within 24 hours of administration.

Conditions Treated

Intravenous Vancomycin is used to treat infections caused by:

Aerobic Gram-Postive Bacteria including:

  • Diphtheroids
  • Enterococci
  • Staphylococcus aureus
  • Staphylococcus epidermidis
  • Staphylococcus bovis
  • Streptococcus viridans
  • Listeria monocytogenes
  • Streptococcus pyogenes
  • Streptococcus pneumoniae
  • Streptococcus agalactiae

Anaerobic gram-positive bacteria including:

  • Acintomyces
  • Lactobacillus

These bacteria cause some well-known conditions including:

  • Pneumonia
  • Lower respiratory tract infections
  • Bone Infections
  • Septicemia
  • Diphtheria
  • Endocarditis
  • Intestinal tract infections
  • Prosthetic heart valve infections

Oral Vancomycin is used to treat:

  • Clostridium Difficile
  • Enterocolitis

Type of Medicine:

  • Antibiotic

Side Effects:

Like the majority of medications, Vancomycin has several possible side effects. Some of these side effects are directly related to the intravenous form of the medication. Those receiving the intravenous form have reported pruritis and urticaria at the injection site. Some have reported a severe, almost immediate allergic reaction after the infusion of the medication. This has led to anaphylactic shock in a limited number of patients. In a few patients, vancomycin will produce flushing throughout the entire body shortly after infusion.

The most numerous reports of side effects with this drug relate to the kidneys, as the drug is eliminated through the kidneys. There have been reports of an increase in the level of certain kidney function tests during prolonged use of Vancomycin. Creatinine and BUN are most often elevated. There are some reports of patients developing interstitial nephritis while taking this medication.

Since vancomycin is a particularly potent antibiotic, there is a risk of gastrointestinal problems when using it. The most serious side effect reported is the development of colitis when using the drug. Almost all antibiotics have the potential to cause gastric upset and diarrhea. However, the diarrhea associated with vancomycin usage can be very serious and needs to be reported to a physician immediately.

Vancomycin has been known to cause side effects involving the inner ear. Patients have reported vertigo, dizziness and balance disturbances. Tinnitus is another possible side effect with vancomycin.

A number of patients have reported several different types of skin reactions while taking this medication. A rash is the main skin side effect. However, patients have also reported instances of exfoliative dermatitis, Stevens-Johnson syndrome, and generalized itching.

There are a few hematological side effect reports. Some patients using vancomycin for long periods may develop neutropenia, thrombocytopenia and agranulocytosis.

Dosage:

The dosage of vancomycin that one receives is usually based on the infective agent and the location and the seriousness of the infection. The normal dosage for adults without any existing kidney problems is two grams of the product administered daily. This dose may be divided as 500 mg every six hours or as one gram given every 12 hours. The drug should be administered over at least a 60 minute period intravenously. This dose may need to be increased based on the patient's weight.

Children without existing kidney disorders receive a different dose; 10mg per kg of weight. This dosage is administered every six hours. As with adults, the dosage should be administered intravenously over at least a 60 minute period.

Those with chronic kidney conditions must be closely monitored while on vancomycin. Normally, the dosage will have to be adjusted. Less of the drug may need to be administered, or the drug may need to be given over a longer period of time.

For most infections, vancomycin will need to be taken for at least a period of seven to 10 days. More serious infections may require treatment for a longer period of time.

As with all antibiotics, vancomycin needs to be taken until the bacteria in the system is eliminated. If the drug is discontinued too soon, there is a risk that the bacteria may return and be even more difficult to bring under control.

Oral vancomycin has a different dosage regimen. Adults with clostridium difficile will take 125mg four times per day for seven to 10 days. Children are given 40 mg per kg divided into four separate doses. Children will also take the medicine for seven to 10 days. Enterocolitis is treated in adults with 500mg four times per day for seven to 10 days. Children receive the same dosage as with clostridium difficile.

Interactions:

There are several different drugs that produce a negative interaction with vancomycin. Doctors recommend that amikasin, gentamicin, piperacillin, and tobramycin not be used at the same time as vancomycin unless absolutely necessary. These medications, when taken with vancomycin, may overtax the kidneys, leading to kidney damage or possible renal failure.

Succinylcholine and warfarin are two drugs that may require a change in dosage if they are used at the same time as vancomycin. They may worsen some of the side effects of vancomycin.

If a patient is taking either Questran or Colestid, they will decrease the effectiveness of vancomycin if they are administered at the same time. These drugs need to be taken at least three hours before or after a dose of vancomycin.

Doctors recommend that patients who are taking vancomycin should avoid using alcohol while on the drug. Alcohol can increase the risk of kidney damage while a patient is taking vancomycin. It can also increase the chances of gastrointestinal side-effects.

Warnings:

As stated, this drug should be used with caution in those patients who have kidney disease. This drug is known to cause severe kidney side effects. Particular care must be exercised when vancomycin is used in children or geriatric patients. Periodic drug serum levels need to be evaluated to make sure that too much of the drug is not building up in the body. This is a signal that the kidneys may not be excreting the drug properly.

Vancomycin is listed as a Pregnancy Category C drug. This means that there has only been a limited amount of testing conducted on the drug. Pregnant women should only receive this drug if it is absolutely necessary. In one study, vancomycin was found in umbilical cord blood. There did not appear to be any effect on the fetus.

Storage:

The intravenous form of vancomycin is stored in a refrigeration unit under 41 degrees Fahrenheit after it has been thawed. It will remain stable and effective for 30 days in refrigeration. At room temperature, the drug will only remain stable for a period of three days.

The oral form of vancomycin should be stored in its child-proof bottle at room temperature. The tablets should not be refrigerated.

Summary:

Vancomycin is an antibiotic drug that comes in both an oral and an intravenous form. Vancomycin is used to treat very serious infections that more common antibiotics are no longer able to treat. Vancomycin in both its oral and intravenous forms is a very powerful medication that does have a number of potentially serious side effects. The most important side effects concern the kidneys as vancomycin is eliminated through the kidneys. If the kidneys do not function properly, too much of the drug may build up in the body leading to toxicity. Most of the other side effects associated with vancomycin are a result of allergic reactions or occur in those patients who have been taking the drug for an extended period of time. Since vancomycin is such a powerful drug, caution needs to be used when children, the elderly or pregnant women take the drug. In these groups, vancomycin should only be used if absolutely necessary.

Vancomycin is normally used for a seven to 10 day period for most conditions. It may be required for a longer period if a person has a very serious condition that is more difficult to treat. Patients should be sure to take the full course of this antibiotic to prevent the recurrence of any bacterial infections.