Macrolide Antibiotics

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Variousmedicines have been developed to act against viral, bacterial andfungal infections. Drugs that work against infectious bacteria aretermed as antibiotics. These types of treatments do not destroyviruses. Macrolides are antibiotics with bacteriostaticcharacteristics. They are capable of killing a broad range ofgram-positive bacteria. These macrolides are widely used, readilyavailable and affordable for the treatment of both mild and moderateinfections. Most of them are taken orally. In some cases, macrolideantibiotics can be applied for the purpose of preventing disease.Unfortunately, some of these macrolides have been associated withliver injury. Two forms of hepatic harm exist. The first one involvesthe increase in the levels of serum aminotransferase. This has beenreported in about 1-5% of patients. The second form is idiosyncratichepatitis with related jaundice. It is characterized by upperquadrant pain and fever. Although rare, it can develop to be moresevere, leading to liver failure and ultimately, death. Some studieshave indicated a possible degree of cross-sensitivity to hepaticdamage during macrolide antibiotic use. However, this phenomenon hasnot been well established (Schlecht &amp Bruno, 2015).


Currently,there are five available macrolide antibiotics in use. They includeerythromycin, clarithromycin, azithromycin, fidaxomicin andtelithromycin. Of these five drugs, erythromycin is a derivative ofthe bacteria Streptomyces erythreus. The other four aresemisynthetic. All these antibiotics have been shown to be effectiveagainst many species of bacteria including streptococci,staphylococci, clostridium, corynebacteria, listeria, Haemophilus andNeisseria among others. In the treatment of illnesses caused bygram-negative bacteria, Helicobacter, Toxoplasma, and mycoplasmapneumonia, Clarithromycin and azithromycin are more efficient thanerythromycin. These two are also more active in the treatment ofcryptosporidia and other atypical mycobacteria. Fidaxomicin is notabsorbed orally. Therefore, it is used in treating diarrhea caused byClostridium difficile. Macrolide antibiotics act by preventingbacteria from synthesizing proteins. Cases of resistance have beenreported during treatment (Andrade &amp Tulkens, 2011). Themedicines are discussed in detail as follows:


Thisis a semisynthetic antibiotic. It rarely causes acute liver injury.Its effectiveness has been shown in the treatment of a wide range ofbacterial infections such as streptococci, staphylococci, clostridia,corynebacteria, listeria, Haemophilus, moxicella and Neisseria. It ismore active than erythromycin in treating Gram-negative bacteria andmycobacteria. This drug was initially approved for use in 1994 and isextensively used to date. Most people tolerate azithromycintreatment, but some develop side effects for instance, nausea,diarrhea, headache, dizziness, edema, and rash [ CITATION Amy15 l 1033 ].


Thisdrug functions similar to the other macrolide antibiotics. In mostscenarios, it is prescribed for respiratory diseases, pneumonia, andskin infections. It can also be used to treat chlamydia pneumoniainfection, helicobacter, and mycobacteria. One negative aspectconcerning this drug is its effect on the liver. It can lead to acuteand at times fatal hepatic damage with jaundice at a rate of 3 in100,000 prescriptions. Allergic reactions are usually absent, andliver injury subsides after cessation of therapy [ CITATION Amy15 l 1033 ].


Thisis one of the oldest macrolide antibiotic used since the 1950s. It isapplied in the treatment of gram-positive bacteria, especially intreating respiratory tract infections, pelvic inflammatory disease,chlamydia infection and amebiasis. One main benefit of this medicineis that it can be prescribed in situations where penicillin,tetracycline, and metronidazole are contraindicated. Side effectsinclude abdominal pain, nausea and sometimes diarrhea. Liver injuryis quite uncommon and is usually self-limiting, especially whentreatment is stopped (Dougherty &amp Pucci, 2012).


Asemisynthetic medicine, Fidaxomicin is used to treat Clostridiumdifficile infections in adults. Its absorption into the system issignificantly diminished hence no link to an elevation of serumenzyme levels. Its use is facilitated by the minimal activity againstnormal intestinal flora. The side effects range from nausea,vomiting, and abdominal pain to diarrhea, hemorrhage, andneutropenia. In some instances, severe adverse effects such as rashand angioedema may occur. Drug-resistant bacterial infections canalso be present. Unlike other macrolides, this medicine is not linkedwith hepatocellular problems since it is not absorbed orally(Dougherty &amp Pucci, 2012).


Thismedication is a ketolide derivative commonly used for the treatmentof community-acquired pneumonia. It was approved for use in 2004, andit is associated with a case of drug-induced liver problems. Due toseveral substitutions made to it, telithromycin has been renderedless susceptible to bacterial strains that are resistant toerythromycin. This drug is vigorous against streptococci,staphylococci, Moraxella, mycoplasma, chlamydia and legionella amongothers. Due to its prospective severe side effects, it is prescribedonly for moderate and serious cases of pneumonia which is communityacquired. Indicated side effects include nausea, dyspepsia, stomachpain, dizziness and body rash. Liver injury due to telithromycin useis characterized by tiredness, jaundice, and fever as well aselevated enzyme levels. Reports of hepatic failure, ascites, hepaticencephalopathy, eosinophilia, and rash can occur [ CITATION Amy15 l 1033 ].

How Work

Bacterialinfection advances as the microorganisms multiply in the body. Thisactivity further increases the intensity of infection. The primaryfunction of macrolides is to prevent the multiplication of bacteria.These drugs achieve this role by inhibiting the synthesis of proteinsessential for bacterial growth and their subsequent propagation.Afterward, they are killed and eliminated by the response of anindividual’s immune system. Clinicians insist on the importance ofcompleting the course of taking antibiotics even after one feelswell. Prior discontinuation should be held strictly under theinstructions of the doctor. Failure to complete the dosage plays avital role in the development of bacterial resistance (Andrade &ampTulkens, 2011). This occurrence means that in the future, treatmentof a similar infection will be hard. These antibiotics must be usedonly when necessary. Diseases caused by viruses for instance coldsand flu cannot be treated using macrolides.


Asmentioned earlier, macrolide antibiotics are effective in thetreatment and prevention of bacterial infections only. Variousconditions are described for antibiotic treatment. These statesinclude nose and throat infections, ear infection, sinusitis,tonsillitis, and laryngitis. Similarly, chest infections, for examplepneumonia, bronchitis, and whooping cough can be taken care of usingthese antibiotics. The medicines can be prescribed for eczema,psoriasis and infected rash among other types of skin infections. Insome cases, mouth and dental infections such as gingivitis and toothabscess can be treated with macrolides. Moreover, the drugs can beprescribed for sexually transmitted diseases for instance Chlamydiaand Neisseria (Schlecht &amp Bruno, 2015).


Somediseases and infections can be prevented through prophylacticmeasures. Macrolide antibiotics have this particular functionalityfor certain types of bacterial infections. An example of suchscenario is where an individual has a sickle-cell disease or hasundergone splenectomy antibiotics have to be taken on a regularbasis to prevent the onset of infection. Likewise, people who haveundergone dental procedures or are at risk of developing an infectionof the heart lining and valves, need to be prescribed withantibiotics (Andrade &amp Tulkens, 2011). However, care must betaken in such situations. All forms of antibiotic medication must beprovided under the close supervision of a qualified healthpractitioner.

OtherUses and Special Considerations

Macrolideantibiotics can be actually used as a perfect alternative topenicillin. As such, people who develop allergic reactions topenicillin-based antibiotics can be given the alternate treatment.Nonetheless, if a person has experienced any form of allergicreactions to macrolides in the past, it is recommended to avoid them.Furthermore, they should not be used by individuals who have geneticblood disorders such as porphyria or a heart rhythm disorder.Individuals with myasthenia gravis are explicitly discouraged fromusing telithromycin. All in all, any person with a kidney and liverproblem should seek more advice before embarking on macrolideantibiotic remedy. Pregnant and lactating mothers can only takeerythromycin throughout that period. Other macrolide antibioticsshould be avoided except in situations where there are no otherappropriate alternatives for treatment (Andrade &amp Tulkens, 2011).

CommonSide Effects

Frequentand general side effects occur in 1 out of 10 people undermedication. They include stomach or intestinal pain, diarrhea, nauseaand sometimes vomiting. If these outcomes become more severe, thenadvanced medical advice should be sought as soon as possible. Theside effects have diminished intensities in azithromycin andclarithromycin compared to the other three drugs. Also, 1 in 100patients may feel dizzy, encounter stomach upsets, indigestion andskin rash. On top of that, between one in 1,000 and one in 10,000 maydevelop rare and less severe effects. These signs include jaundice,arrhythmias, Stevens-Johnson syndrome and tinnitus. Most of thesesymptoms disappear after treatment is complete. It is imperative toavoid participating in certain activities when experiencing one ormore of these side effects [ CITATION Cen13 l 1033 ].A good example is avoiding driving when feeling dizzy.


Medicineshave the potential of altering the effects of another when takensimultaneously. It is imperative to make sure that all drugs are safeto take with antibiotics. For instance, there is a small riskassociated with the use of oral contraceptive pills and macrolideantibiotic treatment. Since this risk cannot be ignored, women areadvised to use extra contraceptive methods such as condoms duringmacrolide therapy and a few days after completing the dosage(Schlecht &amp Bruno, 2015).

Interactionswith Food and Alcohol

Currently,interactions between macrolides and food have not yet beenestablished. But as we have seen, stomach irritation can beexperienced during treatment hence people are encouraged to take themwith food or immediately after eating to reduce the side effect.Likewise, there are no known alcohol-macrolide interactions.Consumption must be as directed by the instruction leaflet or by apharmacist (Schlecht &amp Bruno, 2015).

Missedor Extra Dose

Themissed dose should be taken as soon as possible and continue thecourse as normal. However, if the period for the subsequent treatmenthas arrived, the missed one can be skipped, and the schedule resumes.Double doses are prohibited. If one has taken an extra dose byaccident, the side effects are more likely to be greater in severity.In such a scenario, it is important to contact the clinician forassistance (Andrade &amp Tulkens, 2011).


Antibioticsare valuable pharmaceuticals in the treatment of various bacterialinfections. Macrolide antibiotics have played an important role overthe years in both treatment and prevention of diseases. Despite theireffectiveness, they have their disadvantages concerning side effects.These outcomes may be mild or severe, hence the need to be carefuland seek help in extreme cases. The development of bacterialresistance is a problem that also must be tackled before it gets outof hand, making it difficult to treat subsequent infections.Particular attention must be taken to avoid adverse effect butrather, ensure the best possible outcome is achieved. The mostimportant fact is that the advent of macrolide antibiotics hasprovided a leeway for the management of mild and moderate infectionswhile at the same time reducing the frequency and severity of theside effects.


Andrade, R. J. &amp Tulkens, P. M. (2011). Hepatic safety of antibiotics used in primary care. Journal of Antimicrobial Therapy, 1431-1446.

Centers for Disease Control. (2013). Antibiotic Resistance Threats in the United States. Atlanta: Centers for Disease Control and Prevention.

Dougherty, T. J., &amp Pucci, M. J. (2012). Antibiotic discovery and development. New York: Springer.

Graziani, A. L. (2015, October 28). Azithromycin, clarithromycin, and telithromycin. Retrieved from UpTo

Schlecht, P. H. &amp Bruno, C. (2015, January). Macrolides. Retrieved from Merck Manual:

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