Introduction
Today, people have access to numerous drugs that are useful in treating bacterial infections. Different drugs are characterized by different side effects, metabolic actions, and adverse reactions. Before taking any antibiotic, it is necessary to learn its peculiarities and understand the mechanism of its action. Vancomycin is a glycopeptide antibiotic used to treat various Gram-positive bacterial infections complicated by the presence of an infection of the bloodstream, bone, joint, or skin (Gardete & Tomasz, 2014). In this paper, its mechanism of action, side effects, and adverse reactions will be discussed.
Drug Classification
Vancomycin is an anti-infective antibiotic that belongs to the category of glycopeptides (Gardete & Tomasz, 2014). The peculiar feature of this drug group is the ability to use cell walls construction and blocking as the main method to treat serious and severe infections that are caused by susceptible strains through. The United States has five well-known drug manufacturers that deal with vancomycin, including Baxter Health Care Corporation, Sandoz Incorporated, Hospira Incorporated, APP Pharmaceuticals, Pfizer, and Bioniche Pharma (U.S. Food & Drug Administration, 2017). For example, Pfizer distributes vancomycin as a powder in the following quantities: 500 mg, 1 g, 5 g, 10 g, and 750 mg (Pfizer Injectables, 2017). The quality of this product has been checked and proved by the FDA.
Mechanism of Action
Many academic sources describe the bacterial mechanism of action as based on the process of inhibition of cell-wall biosynthesis. Vancomycin contains substances that help to prevent the incorporation of two types of peptide subunits known as N-acetylmuramic acid (NAM) and N-acetylglucosamine acid (NAG). The combination of NAM- and NAG-peptide subunits leads to the creation of a peptidoglycan matrix that promotes the creation of Gram-positive cell walls. The mechanism of vancomycin’s action is also based on an affinity that this drug shows for D-alanyl and D-alanine (D-ala-D-ala) moieties within the above-mentioned peptides (Gardete & Tomasz, 2014).
Also, this drug participates in RNA synthesis and alters the permeability of bacteria, cells, and membranes (Hu, Peng, & Rao, 2016). As soon as vancomycin reaches the bacterial environment, it begins working to synthesize a new cell wall that may be bound to D-ala-Dala residues.
Metabolism and Excretion
In the latest investigations and research results, many researchers have noted that vancomycin is excreted unchanged in the feces and by the kidneys with no observed metabolism (Kee, Hayes, & McCuistion, 2014) It is thought that vancomycin may also be eliminated by the liver (Alavarez, Cortes, Molina, Cisneros, & Pachon, 2016). Vancomycin clearance depends on the level of creatinine clearance in the body.
A positive value is expected, and the prolongation of vancomycin’s life is possible in the case where vancomycin has a proper molecular weight. However, these reports have not been properly developed and supported. Seventy-five percent of vancomycin is excreted (IV) in the urine, and its half-life is about 4–6 hours (Kee et al., 2014). Therefore, many medical workers, pharmacologists, and nurses accept the fact that the metabolism and excretion of vancomycin will remain unchanged.
Pregnancy Category
Like many antibiotics, vancomycin carries certain pregnancy warnings and explanations. Vancomycin is assigned to Category C, meaning that there is no credible and approved data about the effects of this drug on human pregnancy, and it can be used with caution according to the results obtained from animal studies (Medscape, n.d.). Though there is no evident support for this drug to be used by pregnant patients, harm has not been proven in many cases to date.
The animal-based studies that have been conducted have also been insufficient to prove fetal damage (Medscape, n.d.). Therefore, it is possible to accept a Category B designation in terms of possible minor risks shown through animal studies. Breastfeeding is another important field where the use and appropriateness of vancomycin should be discussed. At this moment, there are not enough credible sources to prove potential harm to a mother or an infant. The possibility remains that the drug may enter the mother’s breast milk, and therefore, this drug is not recommended during breastfeeding.
Common Side Effects and Interventions
According to Kee et al. (2014), vancomycin is characterized by such side effects as vomiting, fever, dizziness, chills, and nausea. A facial rash may also be observed (Medscape, n.d.). Bladder pain and associated urinary problems, including painful or bloody urination, may bother some patients. The possibility of the manifestation of these effects equals 10%. As a rule, the most frequent side effects of vancomycin are fatigue or nausea.
The main intervention that can help patients who suffer these more common side effects is to rest and inform a doctor about any reaction. Pain that does not disappear in one hour makes it imperative to contact a doctor. In the majority of cases, taking ibuprofen or another anti-inflammatory drug with no negative interactions is the suggested course of action. However, even before choosing this kind of intervention, it is important to make sure that a patient does not have any allergies or adverse reactions to vancomycin.
It is necessary to remember that vancomycin has negative outcomes if taken alongside dimenhydrinate, furosemide, aminoglycosides, colistin, or cyclosporine (Kee et al., 2014). Overdose is also a significant factor and may lead to hearing loss, vertigo, and ringing in the ears. However, such cases are rare if a patient takes the prescription as directed and consults a doctor promptly.
Adverse Reactions and Interventions
The evaluation of adverse reactions shows that vancomycin may be dangerous for those who are hypersensitive to this drug. Children should be checked for serum levels before taking this drug. In current studies, it is hard to find effective interventions to respond to the adverse effects of vancomycin. Therefore, the only suggestion that can be given to patients, as well as nurses and other medical workers, is to understand what reactions should be expected.
First, Kee et al. (2014) focus on nephrotoxicity and ototoxicity of the drug, meaning the possibility of renal dysfunction, damage to the vestibular branch of the cranial nerve that leads to temporary loss of balance, or auditory changes that may lead to hearing loss. Eosinophilia is a type of allergic reaction that can be observed in the blood. Some patients may suffer from “red man” syndrome (Kee et al., 2014), in which the affected person displays a red face, neck, or chest as a kind of a toxic outcome.
Such negative reactions as neutropenia, tachycardia, and cardiac arrest must also be mentioned. Though there is only a 1–10% possibility of such adverse reactions, patients and nurses must be prepared for such reactions and be aware of appropriate possible interventions (Medscape, n.d.). However, at present, there are no clear guidelines to follow if a patient faces these kinds of adverse reactions after being treated with vancomycin.
References
Alavarez, R.A., Cortes, L.E.L., Molina, J., Cisneros, J.M., & Pachon, J. (2016). Optimizing the clinical use of vancomycin. Antimicrobial Agents and Chemotherapy, 60(5), 2601-2609.
Gardete, S., & Tomasz, A. (2014). Mechanisms of vancomycin resistance in Staphylococcus aureus. The Journal of Clinical Investigation, 124(7), 2836-2840.
Hu, Q., Peng, H., & Rao, X. (2016). Molecular events for promotion of vancomycin resistance in vancomycin intermediate Staphylococcus aureus. Frontiers in Microbiology, 7(1601). Web.
Kee, J.L., Hayes, E.R., & McCuistion, L.E. (2014). Pharmacology: A patient-centered nursing process approach (8ed.). St. Louis, MO: Elsevier Health Sciences.
Medscape. (n.d.). Vancomycin (rx). Web.
Pfizer Injectables. (2017). Vancomycin hydrochloride for injection, USP. Web.
U.S. Food & Drug Administration. (2017). FDA statement about product quality of parenteral vancomycin products. Web.