Amoxicillin was discovered in 1958 and came into medical use in 1972.[12][13] Amoxil was approved for medical use in the United States in 1974,[4][5] and in the United Kingdom in 1977.[2] It is on theWorld Health Organization's List of Essential Medicines.[14] It is one of the most commonly prescribed antibiotics in children.[15] Amoxicillin is available as ageneric medication.[9] In 2023, it was the 23rd most commonly prescribed medication in the United States, with more than 23million prescriptions.[16][17]
Children with acute otitis media who are younger than six months of age are generally treated with amoxicillin or other antibiotics. Although most children with acute otitis media who are older than two years old do not benefit from treatment with amoxicillin or other antibiotics, such treatment may be helpful in children younger than two years old with acute otitis media that is bilateral or accompanied by ear drainage.[19] In the past, amoxicillin was dosed three times daily when used to treat acute otitis media, which resulted in missed doses in routineambulatory practice. There is now evidence that two-times daily dosing or once-daily dosing has similar effectiveness.[20]
Most sinusitis infections are caused byviruses, for which amoxicillin and amoxicillin-clavulanate are ineffective,[21] and the small benefit gained by amoxicillin may be overridden by the adverse effects.[22]Amoxicillin is considered the first-lineempirical treatment for most cases of uncomplicated bacterial sinusitis in children and adults when culture data is unavailable.[23][24][25] Amoxicillin is recommended as the preferred first-line treatment forcommunity-acquired pneumonia in adults by theNational Institute for Health and Care Excellence, either alone (mild to moderate severity disease) or in combination with amacrolide.[26] Research suggests that is as effective asco-amoxiclav (a broad-spectrum antibiotic) for people admitted to hospital with pneumonia, regardless of its severity.[27][28] TheWorld Health Organization (WHO) recommends amoxicillin as first-line treatment for pneumonia that is not "severe".[29] Amoxicillin is used in post-exposure inhalation ofanthrax to prevent disease progression and for prophylaxis.[18]
Amoxicillin is effective for the treatment of early cutaneousLyme borreliosis; the effectiveness and safety of oral amoxicillin is neither better nor worse than common alternatively-used antibiotics.[32]
Amoxicillin is occasionally used for the treatment of skin infections,[18] such asacne vulgaris.[34] It is often an effective treatment for cases of acne vulgaris that have responded poorly to other antibiotics, such asdoxycycline andminocycline.[35]
Infections in infants in resource-limited settings
Amoxicillin is recommended by the World Health Organization for the treatment ofinfants with signs and symptoms of pneumonia in resource-limited situations when the parents are unable or unwilling to accepthospitalization of the child. Amoxicillin in combination withgentamicin is recommended for the treatment of infants with signs of other severe infections when hospitalization is not an option.[36]
It is also used to preventbacterial endocarditis and as a pain-reliever in high-risk people having dental work done, to preventStreptococcus pneumoniae and otherencapsulated bacterial infections in those withoutspleens, people with damaged spleens (such as some withsickle-cell disease), and for both the prevention and the treatment ofanthrax.[9] The United Kingdom recommends against its use for infectious endocarditis prophylaxis.[37] These recommendations do not appear to have changed the rates of infection for infectious endocarditis.[38]
The onset of anallergic reaction to amoxicillin can be very sudden and intense; emergency medical attention must be sought as quickly as possible. The initial phase of such a reaction often starts with a change in mental state; a skin rash with intense itching (often beginning in the fingertips and around the groin area and rapidly spreading); and sensations of fever, nausea, and vomiting. Any other symptoms that seem even remotely suspicious must be taken very seriously. However, more mild allergy symptoms, such as a rash, can occur at any time during treatment, even up to a week after treatment has ceased. For some people allergic to amoxicillin, the adverse effects can be fatal due toanaphylaxis.[9]
Use of the amoxicillin/clavulanic acid combination for more than one week has caused a drug-induced immunoallergic-typehepatitis in some patients. Young children having ingested acute overdoses of amoxicillin manifestedlethargy, vomiting, andrenal dysfunction.[47][48]
There is poor reporting of adverse effects of amoxicillin from clinical trials. For this reason, the severity and frequency of adverse effects from amoxicillin are probably higher than reported in clinical trials.[11]
Between 3 and 10% of children taking amoxicillin (orampicillin) show a late-developing (>72 hours after beginning medication and having never taken penicillin-like medication previously) rash, which is sometimes referred to as the "amoxicillin rash". The rash can also occur in adults and may rarely be a component of theDRESS syndrome.[49]
The rash is described asmaculopapular or morbilliform (measles-like; therefore, in medical literature, it is called "amoxicillin-induced morbilliform rash".[50]). It starts on the trunk and can spread from there. This rash is unlikely to be a true allergic reaction and is not a contraindication for future amoxicillin usage, nor should the current regimen necessarily be stopped. However, this common amoxicillin rash and a dangerous allergic reaction cannot easily be distinguished by inexperienced persons, so a healthcare professional is often required to distinguish between the two.[51][52]
A nonallergic amoxicillin rash may also be an indicator ofinfectious mononucleosis. Some studies indicate about 80–90% of patients with acuteEpstein–Barr virus infection treated with amoxicillin or ampicillin develop such a rash.[53]
Nonallergic amoxicillin rash eight days after first dose: This photo was taken 24 hours after the rash began.
Eight hours after the first photo, individual spots have grown and begun to merge.
At 23 hours after the first photo, the color appears to be fading, and much of rash has spread to confluence.
It should not be mixed with blood products, orproteinaceous fluids (including proteinhydrolysates) or with intravenous lipid emulsions
aminoglycoside should be injected at a separate site from amoxicillin if the patient is prescribed both medications at the same time. Neither drug should be mixed in a syringe. Neither should they be mixed in an intravenous fluid container or giving set because of loss of activity of the aminoglycoside under these conditions.
Amoxicillin (α-amino-p-hydroxybenzyl penicillin) is a semisynthetic derivative of penicillin with a structure similar to ampicillin but with better absorption when taken by mouth, thus yielding higher concentrations in blood and in urine.[59] Amoxicillin diffuses easily into tissues and body fluids. It will cross theplacenta and is excreted intobreastmilk in small quantities. It is metabolized by the liver and excreted into the urine. It has an onset of 30 minutes and ahalf-life of 3.7 hours in newborns and 1.4 hours in adults.[18]
Amoxicillin was one of severalsemisynthetic derivatives of 6-aminopenicillanic acid (6-APA) developed by theBeecham Group in the 1960s. It was invented by Anthony Alfred Walter Long and John Herbert Charles Nayler, two British scientists.[66][67] It became available in 1972 and was the secondaminopenicillin to reach the market (afterampicillin in 1961).[68][69][70]Co-amoxiclav became available in 1981.[69]
Amoxicillin is relatively inexpensive.[71] In 2022, a survey of eight generic antibiotics commonly prescribed in the United States found their average cost to be about $42.67, while amoxicillin was sold for $12.14 on average.[72]
Anextended-release is available.[6][73] The intravenous form of amoxicillin is not sold in the United States.[74] When an intravenous aminopenicillin is required in the United States, ampicillin is typically used. When there is an adequate response to ampicillin, the course of antibiotic therapy may often be completed with oral amoxicillin.[75]
Amoxicillin is one of the semisynthetic penicillins discovered by the former pharmaceutical companyBeecham Group. The patent for amoxicillin has expired, thus amoxicillin and co-amoxiclav preparations are marketed under various brand names across the world.[1]
Amoxicillin is also sometimes used as anantibiotic for animals. The use of amoxicillin for animals intended for human consumption (chickens,cattle, andswine for example) has been approved.[79]
^"Amoxicillin".www.chemsrc.com.Archived from the original on 19 May 2017. Retrieved8 May 2018.
^abcdefghijklm"Amoxicillin". Drugs.com, The American Society of Health-System Pharmacists. 3 January 2022.Archived from the original on 24 November 2022. Retrieved24 November 2022.
^The selection and use of essential medicines 2023: web annex A: World Health Organization model list of essential medicines: 23rd list (2023). Geneva:World Health Organization. 2023.hdl:10665/371090. WHO/MHP/HPS/EML/2023.02.
^Ahovuo-Saloranta A, Rautakorpi UM, Borisenko OV, Liira H, Williams JW, Mäkelä M (February 2014). Ahovuo-Saloranta A (ed.). "Antibiotics for acute maxillary sinusitis in adults".The Cochrane Database of Systematic Reviews (2) CD000243.doi:10.1002/14651858.CD000243.pub3.PMID24515610.
^abEsposito S, Canevini MP, Principi N (July 2017). "Complications associated with antibiotic administration: neurological adverse events and interference with antiepileptic drugs".Int J Antimicrob Agents.50 (1):1–8.doi:10.1016/j.ijantimicag.2017.01.027.PMID28414069.Benzylpenicillin, the most neurotoxic among the penicillins, has often been associated with the development of encephalopathy and seizures both in animals and humans [21], [22]. However, some neurological adverse effects (anxiety, hyperactivity, confusion, convulsions, and behavioural changes) have also been reported for amoxicillin and ampicillin, the two penicillins with the lowest risk of neurotoxicity [22], [23], [24], [25], [26], [27]. Moreover, ampicillin may cause seizures when administered to very low-birth-weight neonates [28].
^Nestor MA, Ryan M, Cook AM (September 2010). "Catching the seizure culprit: drugs on the differential".Orthopedics.33 (9):679–682.doi:10.3928/01477447-20100722-16.PMID20839747.
^Atli O, Demir-Ozkay U, Ilgin S, Aydin TH, Akbulut EN, Sener E (August 2016). "Evidence for neurotoxicity associated with amoxicillin in juvenile rats".Hum Exp Toxicol.35 (8):866–876.Bibcode:2016HETox..35..866A.doi:10.1177/0960327115607948.PMID26429924.Till date, limited number of acute psychiatric adverse events (including seizure, encephalopathy, and tremor) related to AMX treatment have been reported in patients with no underlying psychiatric disorders.11–15 Furthermore, the Food and Drug Administration has published a report that when AMX was coadministered with cephalosporin, this combination therapy might cause death by inducing seizures in a patient.16
^Cundiff J, Joe S (January 2007). "Amoxicillin-clavulanic acid-induced hepatitis".American Journal of Otolaryngology.28 (1):28–30.doi:10.1016/j.amjoto.2006.06.007.PMID17162128.
^Baselt R (2008).Disposition of Toxic Drugs and Chemicals in Man (8th ed.). Foster City, CA: Biomedical Publications. pp. 81–83.
^"Amoxicillin Rash".Tufts Medical Center. Tufts Medicine MelroseWakefield Hospital. Archived fromthe original on 25 June 2023. Retrieved24 June 2023.
^Barbaud AM, Béné MC, Schmutz JL, Ehlinger A, Weber M, Faure GC (April 1997). "Role of delayed cellular hypersensitivity and adhesion molecules in amoxicillin-induced morbilliform rashes".Archives of Dermatology.133 (4):481–6.doi:10.1001/archderm.1997.03890400081011.PMID9126012.INIST2654598.
^Pichichero ME (April 2005). "A review of evidence supporting the American Academy of Pediatrics recommendation for prescribing cephalosporin antibiotics for penicillin-allergic patients".Pediatrics.115 (4):1048–57.doi:10.1542/peds.2004-1276.PMID15805383.S2CID21246804.
^abcdefReis W, Gaio J, Trang T, Reis H, Tang J, Juma H, et al. (2020). "Antibiotics". In Prabhakar H, Mahajan C, Kapoor I (eds.).Pharmacology in Clinical Neurosciences: A Quick Guide. Singapore: Springer. pp. 265–497.doi:10.1007/978-981-15-3591-8_10.ISBN978-981-15-3591-8.
^Comeau D, Heaton K, Gordon A (January 2012). "Rheumatology and Musculoskeletal Problems". In Rakel RE, Rakel DP (eds.).Textbook of Family Medicine (Eighth ed.). Philadelphia: W.B. Saunders. pp. 648–689.doi:10.1016/b978-1-4377-1160-8.10032-6.ISBN978-1-4377-1160-8.
^abcJafari Ozumchelouei E, Hamidian AH, Zhang Y, Yang M (February 2020). "Physicochemical properties of antibiotics: A review with an emphasis on detection in the aquatic environment".Water Environ Res.92 (2):177–188.Bibcode:2020WaEnR..92..177J.doi:10.1002/wer.1237.PMID31505071.
^Nguyen PT, Le NV, Dinh HM, Nguyen BQ, Nguyen TV (December 2022). "Lung penetration and pneumococcal target binding of antibiotics in lower respiratory tract infection".Curr Med Res Opin.38 (12):2085–2095.doi:10.1080/03007995.2022.2131304.PMID36189961.
^GB patent 978178, Nayler JH, Smith H, "Penicillins", published 16 December 1964, assigned to Beecham Research Laboratories Ltd[permanent dead link]
^Geddes AM, Klugman KP, Rolinson GN (December 2007). "Introduction: historical perspective and development of amoxicillin/clavulanate".International Journal of Antimicrobial Agents.30 (Suppl 2): S109-12.doi:10.1016/j.ijantimicag.2007.07.015.PMID17900874.
^abRaviña E (2014).The Evolution of Drug Discovery. Weinheim: Wiley-VCH. p. 262.ISBN978-3-527-32669-3.
^Bruggink A (2001).Synthesis of β-lactam antibiotics. Springer. p. 17.ISBN978-0-7923-7060-4.
^Farazuddin M, Chauhan A, Khan RM, Owais M (August 2011). "Amoxicillin-bearing microparticles: potential in the treatment of Listeria monocytogenes infection in Swiss albino mice".Bioscience Reports.31 (4):265–72.doi:10.1042/BSR20100027.PMID20687896.
^Ramos F, Boison J, Friedlander LG."Amoxicillin"(PDF).fao.org. Food and Agriculture Organization of the United Nations.Archived(PDF) from the original on 9 October 2022. Retrieved8 November 2019.
