The DOI matches its Crossref record; 5 of the 5 references it cites were found in a registry or an index; none of the 3 sources its claims cite is checked for support yet.
Amoxycillin: A new Semi-synthetic Penicillin
Open accessAbstract
Amoxycillin (alpha-amino-p-hydroxybenzylpenicillin) is a new semi-synthetic penicillin with a broad spectrum of antibacterial activity similar to that of ampicillin. Penicillin-sensitive strains of staphylococci, streptococci, and pneumococci were sensitive to concentrations of 0.1 mug or less of amoxycillin/ml. Strains of Haemophilus influenzae were inhibited by a level of 0.5 mug/ml, and most strains of Escherichia coli, Proteus mirabilis, Shigella sonnei, Salmonella species, and Streptococcus faecalis were sensitive to a concentration of 5 mug or less of amoxycillin/ml. Penicillinase-producing strains of Staphylococcus aureus and strains of Pseudomonas aeruginosa, indole-positive Proteus, Klebsiella, and Enterobacter were insensitive to amoxycillin. The new penicillin was bactericidal in activity, as with other penicillins, and its antibacterial activity was not reduced in the presence of serum. After oral administration to volunteer subjects amoxycillin produced serum concentrations twice as high as those obtained with similar doses of ampicillin, and the penicillin was recovered unchanged in high concentrations in the urine. The absorption of amoxycillin was not greatly influenced by food, and administration of probenecid resulted in increased and more prolonged concentrations of amoxycillin in serum.
Overview
Integrity signals
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Claims the paper makes
23 Own result · 3 Own interpretation · 2 Sources not found · 1 No basis given
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The new penicillin was bactericidal in activity, as with other penicillins”
- Also stated in: § ANTIBACTERIAL ACTIVITY · plain
“Like ampicillin, amoxycillin was bactericidal in activity”
§ Amoxycillin: A new Semi-synthetic Penicillin > Abstract
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § ANTIBACTERIAL ACTIVITY · plain
The paper states this without a source or data behind it here, so there is nothing to check it against. The quote shows it is in the paper.
In the paper
“Penicillinase-producing strains of Staphylococcus aureus and strains of Pseudomonas aeruginosa, indole-positive Proteus, Klebsiella, and Enterobacter were insensitive to amoxycillin.”
§ Amoxycillin: A new Semi-synthetic Penicillin > Abstract
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The absorption and excretion of amoxycillin and ampicillin in fasting subjects was also compared directly in cross-over studies in which the same groups of subjects were given single 250-mg and 500-mg oral doses of the penicillins.”
- Also stated in: § ANTIBACTERIAL ACTIVITY · boosted
“which confirm the data in Table IV- namely, that the mean serum concentrations obtained with amoxycillin were about twice as high as those with ampicillin.”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
boostedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § ANTIBACTERIAL ACTIVITY · boosted
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Strains of Haemophilus influenzae were inhibited by a level of0 5 ,ug/ml”
- Also stated in: § ANTIBACTERIAL ACTIVITY · plain
“Strains of H. influenzae were inhibited by concentrations of both peni- cillins, of 0-1-0{5 tg/ml, amoxycillin being slightly less active than ampicillin.”
§ Amoxycillin: A new Semi-synthetic Penicillin > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § ANTIBACTERIAL ACTIVITY · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The serum concentrations fell relatively rapidly from two hours onwards, reaching quite low levels at six hours.”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“most strains of Escherichia coli, Proteus mirabilis, Shigella sonnei, Salmonella species, and Streptococcus faecalis were sensitive to a concentration of 5 ,ug or less of amoxycillin/ml.”
§ Amoxycillin: A new Semi-synthetic Penicillin > Abstract
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“its antibacterial activity was not reduced in the presence of serum.”
- Also stated in: § ANTIBACTERIAL ACTIVITY · plain
“The antibacterial activity of amoxycillin was not reduced in the presence of 95 % human serum.”
§ Amoxycillin: A new Semi-synthetic Penicillin > Abstract
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § ANTIBACTERIAL ACTIVITY · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The amount excreted in the urine during the six-hour period after administration ranged from 58 to 68% of the dose administered”
- Also stated in: § Discussion · hedged
“60-70% of an oral dose of the compound appears unchanged in the urine.”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § Discussion · hedged
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“the penicillin was recovered unchanged in high concentrations in the urine.”
- Also stated in: § ANTIBACTERIAL ACTIVITY · plain
“bioautographic examination of the urine showed the presence only of unchanged amoxycillin.”
§ Amoxycillin: A new Semi-synthetic Penicillin > Abstract
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § ANTIBACTERIAL ACTIVITY · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“increasing the dose resulted in a corresponding increase in the amoxycillin serum concentrations”
- Also stated in: § Discussion · plain
“Increasing the dose of amoxycillin results in a corresponding increase in serum concentrations”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
- Also stated in: § Discussion · plain
- It may state two separate claims as one. 9
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“amoxycillin serum concentrations of 0-14 F±g/ml at eight hours and 0-08 ,ug/ml at 11 hours were measured after a 250-mg dose to volunteer sub- jects.”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Both penicillins were somewhat less active than benzylpenicillin against sensitive strains of gonococcus, but showed slightly greater activity than the latter against penicillin- insensitive strains.”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The extent of binding of amoxy- cillin to the protein of human serum as measured by ultra- filtration was found to be 17%, leaving 830h of the penicillin in serum as unbound active antibiotic.This degree of binding was similar to that of ampicillin (18% bound) and less than that of benzylpenicillin (59% bound).”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
None of the sources cited for this claim could be matched to a paper in Crossref, so there is nothing to check it against.
In the paper
“Amoxycillin (a-amino-p-hydroxybenzylpenicillin) is a new semi-synthetic penicillin with a broad spectrum of antibacterial activity similar to that of ampicillin.”
- Also stated in: § Introduction · plain
“its antibacterial spectrum and level of activity are similar to those of ampicillin (Neu and Winshell, 1971a; Sutherland and Rolin- son, 1971).”
- Also stated in: § Discussion · plain
“The results presented here show that the antibacterial spectrum and level of in-vitro activity of amoxycillin is similar to that of ampicillin.”
§ Amoxycillin: A new Semi-synthetic Penicillin > Abstract
What the sources say
- Not matchedcites Neu and Winshell, 1971a
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
- Not matchedcites Sutherland and Rolinson, 1971
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
- Also stated in: § Introduction · plain
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The penicillin is relatively stable to acid and a 1% solution at 37°C has a half-life in simulated gastric juice (pH 1X5) of 17 hours compared with a half-life of 12 hours for ampicillin.”
§ Amoxycillin: A new Semi-synthetic Penicillin > Introduction
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Amoxycillin was as active as ampicillin against staphylococci and pneumococci and was slightly more active than the latter against (3-haemolytic streptococci and enterococci.”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Strains of H. influenzae were inhibited by concentrations of both peni- cillins, of 0-1-0{5 tg/ml, amoxycillin being slightly less active than ampicillin.”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
plaindirect- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A result the paper reports from its own data — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“The average concentration of amoxycillin in pooled urine collected over the six-hour period after dosing was 580 Fg/ml (range 50-1,600 [±g/ ml) for the 250-mg dose and 1,100 tug/ml (range 115-1,850 [±g/ ml) for the 500-mg dose.”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
plain- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: unclear — It is unclear whether the paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
A conclusion the paper draws from its own results — it cites no other source for it, so there is none to check. The quote shows it is in the paper.
In the paper
“Ampicillin- resistant strains of Gram-negative bacilli were found to be resist- ant also to amoxycillin, indicating complete cross-resistance between these two penicillins.”
§ Amoxycillin: A new Semi-synthetic Penicillin > ANTIBACTERIAL ACTIVITY
hedgedcorrelational- Asserted: passes — The authors put it forward as true.
- Checkable: passes — It can be checked against evidence.
- Load-bearing: passes — The paper’s conclusions depend on it.
- Based: passes — The paper gives a reason why it holds.
It may state two separate claims as one.
The paper relies on this without support.
In vitro antibacterial activity and serum concentrations of amoxycillin predict its clinical efficacy in treating infections.
“The properties of amoxycillin suggest this new semi-synthetic penicillin may have clinical advantages over ampicillin.”
The paper relies on this without support.
Pharmacokinetic results from healthy volunteers apply to patients.
“The properties of amoxycillin suggest this new semi-synthetic penicillin may have clinical advantages over ampicillin.”
The paper relies on this without support.
The in vitro MIC breakpoints used correspond to clinical susceptibility.
“most strains of E. coli, P. mirabilis, Sh. sonnei, and Salmonella species were sensitive to 5 ,ug or less of amoxycillin/ml.”
“The properties of amoxycillin suggest this new semi-synthetic penicillin may have clinical advantages over ampicillin.”
The paper relies on this without support.
Ampicillin is an appropriate comparator for assessing clinical advantages of amoxycillin.
“Results are reported here to compare the antibacterial activities and absorption and excretion in man of amoxycillin and ampicillin.”
“The properties of amoxycillin suggest this new semi-synthetic penicillin may have clinical advantages over ampicillin.”
Citations
Cites
THE BINDING OF ANTIBIOTICS TO SERUM PROTEINS
Rolinson, G. N., & SUTHERLAND, R. (1965) · British Journal of Pharmacology and Chemotherapy · doi:10.1111/j.1476-5381.1965.tb01788.x · Cited by 152
Self-citationAntimicrobial Agents and Chemotherapy
Perlman, D. (1968) · Science · doi:10.1126/science.160.3827.562 · Cited by 139
Absorption and Excretion of "Penbritin"
Knudsen, E., Rolinson, G. N., & Stevens, S. (1961) · BMJ · doi:10.1136/bmj.2.5246.198 · Cited by 98
Self-citationBritish Journal of Pharmacology and Chemotherapy
(2012) · British Journal of Pharmacology and Chemotherapy · doi:10.1111/(issn)1476-5381a · Cited by 67
Derivatives of 6-aminopenicillanic acid. XI. Alpha-amino-p-hydroxybenzylpenicillin.
Long, A. A., Jh, N., Smith, H., et al. (1971) · PubMed · Cited by 9
Research works printed but not linked: 3
- [2]2. Penicillin Ampicillin Il I on 19 August 2023 by guest. Protected by copyright. http://www.bmj.com/ Br Med J: first published as 10.1136/bmj.3.5817.13 on 1 July 1972. Downloaded from References
- [6]6. Long, A. A. W., Nayler, J. H. C., Smith, H., Taylor, T., and Ward, N. (1971). Journal of the Chemical Society, Section C, p. 1920.
- [10]10. Sutherland, R., and Rolinson, G. N. (1971). Antimicrobial Agents and Chemotherapy, 1970, p. 411. on 19 August 2023 by guest. Protected by copyright. http://www.bmj.com/ Br Med J: first published as 10.1136/bmj.3.5817.13 on 1 July 1972. Downloaded from
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An Overview of Drug Discovery and Development
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Oral amoxicillin and amoxicillin–clavulanic acid: properties, indications and usage
Huttner, A., Bielicki, J. A., Clements, M., Møller, J. K., Muller, A. E., Paccaud, J. P., & Mouton, J. W. (2019) · Clinical Microbiology and Infection · doi:10.1016/j.cmi.2019.11.028 · Cited by 280
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Brogden, R. N., Pinder, R. M., Sawyer, P. R., Speight, T. M., & Avery, G. S. (1976) · Drugs · doi:10.2165/00003495-197612030-00002 · Cited by 195
Metadata
- Authors
- Sutherland, R., Croydon, E. A. P., & Rolinson, G. N.
- Affiliations
- University of Oxford (GB)
- Venue
- BMJ
- Publisher
- BMJ
- Published
- 1972-07-01
- Volume
- 3
- Issue
- 5817
- Pages
- 13-16
- ISSN
- 0007-1447 (ISSN-L)
- 1468-5833
- OpenAlex
- W1969572602
- Semantic Scholar
- 389d3638695c8b7463640e3fa701119172c511a2
- Cited by
- 178
- References
- 5
- Citations by year
- 2026: 1 · 2025: 4 · 2024: 3 · 2023: 4 · 2022: 3 · 2021: 2 · 2020: 9 · 2019: 8 · 2018: 4 · 2017: 5 · 2016: 1 · 2015: 3 · 2014: 3 · 2013: 2
- FWCI
- 15.93
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Licence
- www.bmj.com/company/legal-information/terms-conditions/legal-information/tdm-licencepolicy (tdm)
- Locations
- BMJ (publishedVersion)
- PubMed (publishedVersion)
- HighWire Press Open Archive (submittedVersion)
- Topics
- Health Sciences › Medicine › Pharmacology (medical) › Antibiotics Pharmacokinetics and Efficacy
- Health Sciences › Medicine › Microbiology (medical) › Antibiotic Resistance in Bacteria
- Health Sciences › Medicine › Pharmacology (medical) › Historical Medical Research and Treatments
- Keywords
- amoxicillin, semisynthetic penicillins, antibacterial activity, bactericidal activity, serum stability, oral bioavailability, urinary excretion, probenecid, drug interactions, Staphylococcus aureus, Pseudomonas aeruginosa, Haemophilus influenzae, ampicillin comparison
- MeSH terms
- Administration, Oral, Amines, Benzyl Compounds, Enterobacteriaceae, Escherichia coli, Food, Haemophilus influenzae, Humans, Klebsiella, Microbial Sensitivity Tests, Penicillin Resistance, Penicillins, Phenols, Probenecid, Proteus, Pseudomonas, Salmonella, Shigella sonnei, Staphylococcus, Streptococcus, Enterococcus faecalis, Streptococcus pneumoniae
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- The paper
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