β-lactam; cell wall synthesis
Glutamate transporter 1 (GLT-1) [3]

Ampicillin has a dose-dependent effect on swine-derived E. Coli growth inhibition. Ampicillin's effective inhibitory concentration was 2.5 uG/mL[1].

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In vitro susceptibility testing of 103 E. coli isolates from pigs showed that 100 isolates were completely susceptible to Ampicillin at a concentration of 5.0 µg/mL in nutrient broth, while 3 isolates were resistant. [1]
All 4 Salmonella isolates from a case of necrotic enteritis were completely susceptible to 5.0 µg/mL of Ampicillin. [1]
When fecal samples from pigs were plated on E.M.B. agar containing Ampicillin, no inhibitory effect on E. coli growth was observed at concentrations of 0, 0.1, and 1.0 µg/mL. Concentrations of 2.5, 5.0, and 10.0 µg/mL progressively inhibited E. coli growth in a dose-dependent manner. [1]
All E. coli isolates tested with a 10 µg Ampicillin sensitivity disc showed clear zones of inhibition, indicating susceptibility. The inhibition zones around the Ampicillin disc were larger than those around 30 µg chlortetracycline or oxytetracycline discs. [1]

When hemorrhagic enteritis strikes an 11-week-old pig, ampicillin works wonders to relieve the symptoms[1]. Maximum concentrations of ampicillin are twice as high in bile as they are in serum. After an oral dosage, the peak concentration of ampicillin in portal blood is twice as high as in peripheral blood[2]. Neuroprotection against brain damage caused by ischemia-reperfusion is offered by ampicillin. Ampicillin raises the level of GLT-1 expression while decreasing MMP activity. After global forebrain ischemia, pretreatment with ampicillin dramatically lowers medial hippocampal cell death[3].

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Oral administration of Ampicillin to an 11-week-old pig with hemorrhagic enteritis resulted in clinical improvement within 6 hours and complete recovery within 48 hours. [1]
Following treatment, the serotype O141 of E. coli associated with enteritis disappeared from the fecal flora and was replaced by an aberrant E. coli type capable of producing H₂S. [1]
No Ampicillin-resistant E. coli strains emerged after treatment. [1]

SENSITIVITY TESTING[1]
A set of 5 replicate tubes at each concentration of the antibiotic were inoculated with one drop each of an 18 hour growth of the test culture. The inoculated tubes were incubated at 37°C. for 6 hours, after which further growth was stopped by mixing formalin at 0.5% final concentration. Growth of cultures was recorded as the optical density, employing a Fisher Electrophotometer3 with a 525 m.u. filter.

The in vitro susceptibility of 103 cultures of E. coli isolated from scouring and nonscouring pigs, and four cultures of Salmonella isolated from a case of necrotic enteritis was tested against Ampicillin contained in nutrient broth at concentrations of 0, 0.1, 1.0 and 5.0 uG per ml. of the medium. All but three cultures of E. coli were found to be susceptible to 5.0 uG/ml., all Salmonella isolates were also susceptible to this concentration of the antibiotic. Susceptibility of E. coli was also tested by plating dilutions of fecal samples obtained from either a scouring or a nonscouring pig, with E.M.B. agar containing 0, 0.1, 1.0, 2.5, 5.0 and 10.0 uG Ampicillin per ml. of the medium. No difference in the growth of E. coli was observed at 0, 0.1 and 1.0 uG concentrations. The three higher concentrations of the antibiotic inhibited the growth of E. coli proportional to the amount of Ampicillin in each concentration. Ampicillin proved very effective in alleviating the symptoms of hemorrhagic enteritis in a 11-week old pig. The disappearance of scours was associated with the replacement of the previously existing sero-biotypes of fecal E. coliwith another aberrant type of E.coli which produced H2S. No Ampicillin resistant strains of E. coli emerged following treatment of the animal with this antibiotic.[1]

Mice: Normal saline is used to dissolve ampicillin. After receiving halothane anesthesia, male C57BL/6 mice had their common carotid arteries blocked bilaterally for 40 minutes. Penicillin G (6,000 U/kg or 20,000 U/kg, intraperitoneally [i.p.]) or ampicillin (200 mg/kg) was given intraperitoneally (i.p.) every day for five days prior to transient forebrain ischemia. The same volume and timing of saline administration were used for the control animals[3].

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An 11-week-old pig with hemorrhagic enteritis was treated orally with Ampicillin administered in gelatin capsules. The dosing regimen consisted of an initial dose of 8 mg/kg body weight, followed by two additional doses of 4 mg/kg each at 4-hour intervals. [1]
Fecal samples were collected from the pig before treatment and 48 hours after the first dose. A fecal sample from a healthy pig from another litter was also collected as a control. [1]

Absorption, Distribution and Excretion
Ampicillin is primarily excreted unchanged in the urine. Incomplete absorption occurs when ampicillin is taken before eating. It appears in the bile, undergoes enterohepatic circulation, and is excreted in the feces. Bile concentrations depend on the integrity of the gallbladder and its bile ducts. After absorption from the gastrointestinal tract or injection site, ampicillin is distributed to the liver, bile, muscles, kidneys, crop, and adipose tissue. Ampicillin has been used to treat and prevent salmonellosis in avian birds with encouraging results. Ampicillin is excreted via bile. Anhydrous ampicillin and ampicillin trihydrate are generally stable in acidic gastric juices. In fasting adults, 30-55% of the dose is absorbed from the gastrointestinal tract after oral administration. Although peak serum concentrations are reached within 1 hour of administration, maximum serum concentrations are typically reached after approximately 2 hours.
Two hours after oral administration of 250 mg ampicillin to fasting subjects, the mean peak serum concentration was 1.8–2.9 μg/mL. After oral administration of 500 mg, the mean peak serum concentration was 3–6 μg/mL. Six hours after oral administration of 500 mg, the serum antibiotic concentration was less than 1 μg/mL.
For more complete data on absorption, distribution, and excretion of ampicillin (16 items in total), please visit the HSDB record page.

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Metabolism/Metabolites
Ampicillin is degraded by penicillinase…
In Bacillus and Penicillium, it produces α-aminobenzylpenicillic acid; in Escherichia coli, it produces L-phenylglycine. /Excerpt from Table/
Approximately 20% of a given dose (250–500 mg) of ampicillin is metabolized in healthy subjects. Within 12 hours, 7% of the total dose is excreted in the urine as metabolites… Ampicillin is metabolized to 5R,6R-penicillic acid and 5S,6R-penicillic acid… After oral administration, it is metabolized to piperazine-2,5-dione… Other unidentified metabolites have also been reported…

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Biological Half-Life
The half-life of all aminopenicillins is approximately 60–90 minutes.
After intraperitoneal injection…the serum half-life of ampicillin is estimated to be 27 minutes…
…The plasma half-life of ampicillin is usually 1–2 hours…but longer in the elderly…in patients with renal failure, the half-life can be as long as 20 hours…

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The literature cited in this study mentions that ampicillin is well absorbed after oral administration and is quite stable when dissolved in water. [1]
Other data show that after oral administration, the highest concentrations of ampicillin are found in the liver and kidneys, with concentrations in urine and bile being 800 times and 300 times higher than in blood, respectively. [1]

Hepatotoxicity
Rare cases of specific liver injury have been reported in patients taking aminopenicillin antibiotics. The incidence with ampicillin is much lower than with amoxicillin, possibly occurring in one in 100,000 exposed individuals. These cases are characterized by a short incubation period, ranging from a few days to two weeks. Liver injury can occur after discontinuation of the antibiotic. Serum enzyme profiles associated with aminopenicillin-induced liver injury include hepatocellular types, characterized by significantly elevated ALT and AST, and mildly elevated alkaline phosphatase, which rapidly recovers upon discontinuation. Additionally, cholestatic liver injury has been reported, characterized by significantly elevated alkaline phosphatase (similar to penicillin-induced liver injury), some of which are associated with prolonged cholestasis, and in rare cases, disappearance of bile duct syndrome. Liver injury may be accompanied by rash, toxic epidermal necrolysis, or Stevens-Johnson syndrome. Autoantibodies are uncommon. Probability score: C (likely, but rarely, to cause clinically significant liver injury).

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Effects during pregnancy and lactation>
◉ Overview of medication use during lactation
Extensive information suggests that the concentration of ampicillin in breast milk is low and is not expected to have adverse effects on breastfed infants. There are reports that penicillin-type drugs occasionally disrupt the infant's gut microbiota, leading to diarrhea or thrush, but these effects have not been fully assessed. Breastfeeding women can take ampicillin.
◉ Effects on breastfed infants
An uncontrolled observational study of infants breastfed by mothers taking ampicillin appeared to have an increased incidence of diarrhea and candidiasis, attributed to ampicillin in breast milk.
In a prospective follow-up study, 5 breastfeeding mothers reported taking ampicillin (dosage not specified). One mother reported her infant developing diarrhea. No rashes or candidiasis were reported in infants exposed to ampicillin.
A small, controlled prospective study required mothers to monitor their infants for signs of adverse reactions (thickened tongue coating, feeding difficulties, changes in stool frequency and consistency, diaper rash, and skin rash). Weight changes and the occurrence of jaundice were also documented. No statistically significant differences were found in these parameters between infants born to mothers in the control group and infants born to mothers taking ampicillin.
◉ Effects on breastfeeding and breast milk
No relevant published information was found as of the revision date.

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Interactions...Ampicillin...mixed with gentamicin in vitro.../prolonged/leads to loss of antibacterial activity of gentamicin.
Concomitant administration of penicillin and probenecid can lead to higher and longer-lasting serum antibiotic concentrations. Ampicillin has been shown to have similar interactions.
Gentamicin-related drugs...kanamycin, neomycin, and tobramycin may interact with carbenicillin.
Limited data suggest that concomitant administration of high-dose aspirin with penicillin increases serum penicillin concentrations and half-life. Although studies have shown that the co-administration of high-dose aspirin can enhance the clinical efficacy of penicillin, the potential toxicity of high-dose aspirin makes this therapy unsuitable. /Penicillin/
For more complete data on interactions of ampicillin (21 in total), please visit the HSDB record page.

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Non-human toxicity values>
Oral LD50 in rats: 10 g/kg body weight
Oral LD50 in mice: 15.2 g/kg body weight
Intraperitoneal LD50 in 1-day-old rats: 3300 mg/kg body weight
Intraperitoneal LD50 in 83-day-old rats: 4500 mg/kg body weight
The literature cited in this study indicates that ampicillin has low toxicity, based on a report of 28 patients treated with the drug for 5 days or longer without significant toxicity. [1]

[1]. Effect of Ampicillin on E. Coli of Swine Origin. Can J Comp Med Vet Sci. 1963 Sep;27(9):223-7.

[2]. Ampicillin in portal and peripheral blood and bile after oral administration of ampicillin andpivampicillin. Eur J Clin Pharmacol. 1974;7(2):133-5.

[3]. The neuroprotective mechanism of ampicillin in a mouse model of transient forebrain ischemia. Korean J Physiol Pharmacol. 2016 Mar;20(2):185-92.

Ampicillin is a penicillin with a 2-amino-2-phenylacetamido group at the 6-position of its penicillin ring. It is an antibacterial drug. It is both a penicillin and a penicillin allergen, as well as a β-lactam antibiotic. It is the conjugate acid of ampicillin (1-). Ampicillin is a semi-synthetic derivative of penicillin and can be used as an orally effective broad-spectrum antibiotic. Ampicillin belongs to the penicillin class of antibacterial drugs. Ampicillin has been reported in Microsphaeropsis arundinis, Aspergillus banksianus, and other microorganisms with relevant data. Ampicillin is a broad-spectrum, semi-synthetic β-lactam penicillin antibiotic with bactericidal activity. Ampicillin binds to and inactivates penicillin-binding protein (PBP) located on the inner membrane of bacterial cell walls. Inactivation of PBP interferes with the cross-linking of peptidoglycan chains, which is crucial for maintaining the strength and rigidity of bacterial cell walls. This disrupts bacterial cell wall synthesis, leading to reduced cell wall strength and ultimately cell lysis. Ampicillin is stable against the hydrolytic activity of various β-lactamases, thus it can be used to treat infections caused by a variety of Gram-positive and Gram-negative bacteria. A semi-synthetic penicillin derivative, it is an orally effective broad-spectrum antibiotic. Indications: For the treatment of infections caused by Escherichia coli, Proteus mirabilis, Enterococcus, Shigella, Salmonella typhi and other Salmonella, non-penicillinase-producing Neisseria gonorrhoeae, Haemophilus influenzae, Staphylococcus, and Streptococcus (including Streptococcus spp.) (respiratory tract infections, gastrointestinal infections, urinary tract infections, and meningitis). Mechanism of Action: Ampicillin inhibits the third (and final) stage of bacterial cell wall synthesis by binding to specific penicillin-binding proteins (PBPs) located within the bacterial cell wall. Cell lysis is mediated by bacterial cell wall autolysins (such as autolysins); ampicillin may interfere with the action of autolysin inhibitors. Since penicillin has no effect on existing cell walls, its bactericidal effect is only apparent when bacteria are multiplying. /Penicillin/
Penicillin and its metabolites are potent immunogens because they can bind to proteins and act as haptens to trigger an acute antibody-mediated immune response. The most common (approximately 95%) or "primary" determinant of penicillin allergy is the penicillin acyl determinant, which is produced by opening the β-lactam ring of penicillin. This allows penicillin to bind to proteins via the amide group. "Minor" determinants (occurring less frequently) refer to other metabolites, including native penicillin and penicillinic acid. /Penicillin/
Bactericidal agent; inhibits bacterial cell wall synthesis. Its action depends on whether penicillin can reach and bind to penicillin-binding proteins located on the inner membrane of the bacterial cell wall. Penicillin-binding proteins (including transpeptidase, carboxypeptidase, and endopeptidase) are enzymes involved in the final stages of bacterial cell wall assembly and in the remodeling of the cell wall during bacterial growth and division. Penicillin binds to and inactivates these penicillin-binding proteins, leading to a weakened bacterial cell wall and eventual lysis. /Penicillin/

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Therapeutic Uses
Penicillin
For mild to moderate illness, oral administration…Adults…1-4 grams daily, divided into equal doses…every 6 hours. For severe infections…parenteral administration is preferred…6-12 grams daily. …Meningitis requires…children parenteral administration of 300-400 mg/kg/day (divided into equal doses…every 4 hours), adults 12 grams or more daily.
Dosage varies depending on the type and severity of infection, renal function, and…age. For children…dosage should not be determined based on weight or body surface area; since this drug is primarily excreted by the kidneys, renal function largely determines the dosage. Infants and young children require small doses; the dosage for children aged 3-4 years is almost the same as for adults.
Ampicillin is indicated for the treatment of acute otitis media caused by susceptible bacteria. (Included in the US product label)
For more complete data on the therapeutic uses of ampicillin (of 18 types), please visit the HSDB record page.

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Drug Warnings
There has been one case of fatal pseudomembranous colitis after 5 days of oral ampicillin at 2 g/day.Ampicillin rarely causes interstitial nephritis; one case of interstitial nephritis has been reported to progress to acute renal failure. …Crystallization has been reported…
During long-term treatment, especially in premature infants, newborns, and other infants, renal, hepatic, and hematopoietic functions should be assessed regularly.
Absorption efficiency and elimination rate of ampicillin…decreased in patients with Shigella infection. Malabsorption…commonly seen in young patients with significant diarrhea. …Delayed excretion. Plasma drug concentrations are significantly elevated in patients with renal failure. This article discusses the National Registry of Drug Warnings for Eyes, established by the U.S. Food and Drug Administration (FDA) in 1975. This registry aims to alert physicians to the potential eye side effects of certain medications, such as ampicillin. For more complete data on ampicillin warnings (16 in total), please visit the HSDB records page.

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Pharmacodynamics
Ampicillin is a penicillin-type β-lactam antibiotic used to treat bacterial infections caused by susceptible bacteria, typically Gram-positive bacteria. The term "penicillin" can refer to several available penicillin derivatives or to the class of antibiotics derived from penicillin. Ampicillin exhibits in vitro activity against Gram-positive, Gram-negative aerobic, and anaerobic bacteria. Its bactericidal activity derives from its inhibition of cell wall synthesis and its action through binding to penicillin-binding proteins (PBPs). Ampicillin is stable against the hydrolytic activity of a variety of β-lactamases, including penicillinase, cephalosporinase and extended-spectrum β-lactamase. Ampicillin is a synthetic penicillin with broad-spectrum antibacterial activity against both Gram-positive and Gram-negative bacteria. Its antibacterial spectrum is similar to that of tetracycline antibiotics. [1] It has been reported that ampicillin has higher activity against Gram-negative bacteria than tetracycline and chloramphenicol, and retains most of its bactericidal activity in the presence of serum. [1] This study shows that ampicillin can effectively relieve the symptoms of hemorrhagic enteritis in pigs, and no drug-resistant Escherichia coli strains were observed after a single course of treatment. [1] In vitro experiments showed that the effective inhibitory concentration of ampicillin against porcine Escherichia coli was 2.5 µg/mL. [1]

C16H19N3O4S

349.40476

349.109

C, 55.00; H, 5.48; N, 12.03; O, 18.32; S, 9.18

69-53-4

Ampicillin sodium;69-52-3;Ampicillin trihydrate;7177-48-2;Ampicillin-d5;1426173-65-0; Ampicillin;69-53-4;Ampicillin trihydrate;7177-48-2; 69-53-4 (free acid); 23277-71-6 (potassium); 114977-84-3 (trimer trisodium) ; 69-52-3 (sodium); 7490-86-0 (hemisulfate); 33276-75-4 (benzathine); 119229-01-5 (embonate); 40688-84-4 (HCl)

6249

White to off-white solid powder

1.6±0.1 g/cm3

644.5±65.0 °C at 760 mmHg

198-200 °C (dec.)(lit.)

343.6±34.3 °C

0.0±2.0 mmHg at 25°C

1.724

1.65

3

6

4

24

562

4

OC([C@@H]1N(C2=O)[C@]([C@@H]2NC([C@@H](C3=CC=CC=C3)N)=O)([H])SC1(C)C)=O

AVKUERGKIZMTKX-UHFFFAOYSA-N

InChI=1S/C16H19N3O4S/c1-16(2)11(15(22)23)19-13(21)10(14(19)24-16)18-12(20)9(17)8-6-4-3-5-7-8/h3-7,9-11,14H,17H2,1-2H3,(H,18,20)(H,22,23)

(2S,5R,6R)-6-[[(2R)-2-amino-2-phenylacetyl]amino]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid

Aminobenzylpenicillin; 69-53-4; Ampicillin; Aminobenzylpenicillin; Ampicillin acid; Tokiocillin; Omnipen; Amcill; Ampicillin Anhydrous; Ampicillin acid; Principen; Amcill;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

0.1 M NaOH : ~25 mg/mL (~71.55 mM)
H2O : ~4.9 mg/mL (~14.02 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)