What is Vancomycin?
Vancomycin is a drug that is beneficial in the case of life-threatening bacterial infections and it can by administered as Vancomycin IV , oral or inhalation. To be precise, the medical issues occurring because of Gram-positive bacteria and are not cured by the other antibiotics, are effectively treated with this antibiotic. This glycopeptide antibiotic operates by blocking cell wall construction. It is not meant for viral infections.
Edmund Kornfeld was the first person to isolate Vancomycin in the year 1953 from the soil sample of Borneo. It is made using the soil bacterium Amycolatopsisorientalis. The initial name under which Vancomycin Hydrochloride was marketed by Eli Lilly was Vancocin. It came into the market in the year 1954. The World Health Organization has categorized it as the health system’s most effective and safe medicines.
The drug ceases bacterial growth when administered as Vancomycin IV . The oral vancomycin dosage is also available for treating colitis which might occur after the antibiotic treatment. Diarrhea and discomfort in the stomach in Colitis is dealt with, by remaining in the intestine to prevent further bacterial growth.
Modes of administration of Vancomycin:
1. Intravenous Vancomycin
The general mode of administration of this antibiotic is through the veins since it doesn’t get absorbed from the intestines. Its half-life is short that necessitates injecting it twice. The patient’s medical conditions such as his/her blood reports, weight as well as his response towards the treatment determine the exact Vancomycin IV dose.
The Vancomycin dilution for IV needs to be slowly administered for an hour at a 10mg/min when the dose is more than 500mg. This is important to avoid pain and thrombophlebitis. It can also cause “red man syndrome” or “red neck syndrome”, 4-10 minutes after the infusion is over. This results in rashes on the face, neck and upper torso. The patient might also experience hypotension and angioedema. In order to treat or prevent such symptoms, anti-histamines are used.
2. Oral vancomycin dose
When the oral dose of Vancomycin is taken, it is not very effective because of poor absorption. It is mixed with water and then taken through the mouth. Taking it at equally spaced intervals makes it effective and prevents the patient from missing any dose.
3. Inhaling (off-label):
Inhaling Vancomycin is the off-label use of the antibiotic through a nebulizer. It treats different infections related to the upper as well as the lower respiratory tract.
Vancomycin has biexponential distribution, moderate hydrophilicity, and chances for ototoxicity and nephrotoxicity. It is highly probable in the patients prone to bacterial infection and those with low renal function. This necessitates plasma level monitoring. It is applicable in case of patients on hemodialysis, those with altered pharmacokinetic parameters, reduced renal function. The method is also used for those under concomitant aminoglycoside therapy.
Uses of Vancomycin:
Vancomycin has the following medical uses:
1. Treatment of serious infections in the skin.
2. Endocarditis treatment in case of the patients who are hypersensitive to penicillin
3. Infections in the bone and joints
4. For treating Methicillin-resistant Staphylococcus Aureus(MSRA) induced meningitis.
5. Infections in the bloodstream
6. Treatment of Clostridium Difficile induced Colitis through the oral dosage when them Metronidazole treatment doesn’t work.
7. To a certain extent, Vancomycin stops the progression of primary sclerosing cholangitis as well as prevents its symptoms. But the complete cure is not possible with it.
8. For prevention of endophthalmitis through intravitreal injection for gram-positive bacteria coverage. This is known to have certain side effects.
9. Treatment of persons who are allergic to beta-lactam antimicrobials, suffering from Gram-positive microorganism- induced infections.
Vancomycin is the only treatment in case of sepsis and infection in the lower respiratory tract occurring because of the same bacteria.
Side effects of this drug:
Here are the common side effects of this antibiotics that a patient may experience:
1.Pain in the injected area along with allergic reactions and thrombophlebitis.
2. Chances of loss of hearing power.
3.Fall in the blood pressure
4. Bone marrow suppression
The rare side effects include:
1. Chances of nephrotoxicity which occurs only in 0.1%-1% of patients. But this increases in the presence of aminoglycosides.
3. Toxic epidermal necrolysis
4. Erythema multiforme
5. Red man syndrome
7. The occurrence of bleeding with florid petechial hemorrhages
13. DRESS syndrome
14. Chances of platelet-reactive antibodies formation
that causes severe thrombocytopenia
16. Wet Purpura
Resistance to the antibiotic:
There are certain cases of intrinsic resistance to this antibiotic, which are as follows:
1. Leuconostoc and Pediococcus species are the gram-positive bacteria which has intrinsic resistance towards this drug but they rarely cause diseases in humans.
2. Most of the Lactobacillus species except L. acidophilus and L. Delbruekii.
3. Other gram-positive bacteria which are resistant to it are Erysipelothrixrhusiopathiae, Weissellaconfusa, and Clostridium Innocuum
4. Most of the Gram-negative bacteria are intrinsically resistant to it since their outer membranes do not allow the large glycopeptide molecules
In the hospitals, we can find increasing cases of the microbial resistance to this antibiotic. Linezolid and Daptomycin are new alternatives to this drug. But since Vancomycin has widely prevalent uses it becomes a concern when resistance to it develops. This is quite worrisome for those patients when the identification of resistant infections are not possible soon because of which the unproductive treatment continues.
In the year 1987, the emergence of Vancomycin-resistant Enterococcus occurred. Then its resistance emerged in the common pathogenic organisms such as Vancomycin-intermediate S. aureus (VISA) and Vancomycin-resistant S. aureus (VRSA), during the 1990s and 2000s. Another important cause of vancomycin-resistant organisms evolution is the agricultural use of Avoparcin or similar glycopeptide antibiotics.
Among the Enterococcus Faecium and E. Faecalis which are resistant to Vancomycin, there are 3 kinds of resistant variants, namely:
1. Van A – Enterococcal resistance occurs when exposed to Vancomycin and Teicoplanin.
2. Van B – Vancomycin induces a low-level enterococcal resistance, though the strains are susceptive to Teicoplanin.
3. Van C – It is only resistant to Vancomycin and constitutive resistance.
Reasons for not using Vancomycin as the first-line treatment for S.Aureus:
1. Its oral bioavailability is low as its intravenous injections are available for treating infections.
2. The development of methicillin, which is β-Lactamase-resistant semisynthetic penicillin, was found to be more effective against non-MRSA Staphylococci.