When the concentration of antibiotic is less than the MIC (minimum inhibitory concentration) of 0.70 μg/mL at pH 7.4 and pH 5.5, cefradine (0~8 μg/mL; 12 hours) can quickly boost bacterial viability [4].

Cefradine (25 mg/kg; subcutaneous; 11 days) lowers bacterial density and counts in abscesses [4].

Animal/Disease Models: Non-diabetic mice
Doses: 25 mg/kg
Route of Administration: Sc; 11 days
Experimental Results: diminished bacterial density and counts in abscesses.

Absorption, Distribution and Excretion
Over 90% of the drug is excreted unchanged in the urine within 6 hours. Oral Cephradine is almost completely absorbed; food slows the absorption rate but does not decrease it. After oral administration of 250 mg and 500 mg on an empty stomach, peak plasma concentrations within 40 minutes are approximately 9 μg/mL and 16.5 μg/mL, respectively. Intramuscular absorption is significantly slower. Following a single oral dose, Cephradine is rapidly absorbed from the gastrointestinal tract and reaches peak serum concentrations within 1 hour. 75-100% of the dose is excreted unchanged in the urine within the first 6 hours. Six subjects received 1 g of Cephradine (I) and 1 g of cephalexin (II) every 4 hours for a total of 7 doses; five subjects received 2 g every 6 hours for a total of 5 doses. After 1 g administration, peak serum concentrations for I and II were 29 and 35 μg/mL, respectively; after 2 g administration, peak serum concentrations were 45-50 μg/mL.
Cephalosporins are primarily excreted via the kidneys… /Cephalosporins/
For more complete data on the absorption, distribution, and excretion of Cephradine (18 in total), please visit the HSDB record page.

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Metabolism/Metabolites
Cephalosporins are not metabolized; they are rapidly absorbed from the gastrointestinal tract and excreted unchanged in the urine.

Effects During Pregnancy and Lactation
◉ Overview of Use During Lactation
Limited information suggests that low concentrations of Cephradine in breast milk are not expected to have adverse effects on breastfed infants. There are reports that cephalosporins occasionally disrupt the infant's gut microbiota, leading to diarrhea or thrush, but these effects have not been fully assessed. Cephradine can be used in breastfeeding women.
◉ Effects on Breastfed Infants
No relevant published information was found as of the revision date.
◉ Effects on Lactation and Breast Milk
No relevant published information was found as of the revision date.

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Interactions
…When…cephalosporins and peptide antibiotics are used concurrently…renal function parameters should be monitored. /Cephalosporins/
These uricosuric agents can affect…the excretion of weakly acidic urine. Therefore…concurrent use of probenecid or sulfinpyrazone may affect the efficacy of cephalosporins. Cephalosporin antibiotics: Gentamicin and cefotaxime, whether used concurrently or alone, may increase the risk of nephrotoxicity and acute renal failure. ... Unless there is a life-threatening situation, gentamicin should not be used in combination with cefotaxime or other parenteral cephalosporins (such as Cephradine). Studies have found that acetaldehyde at in vivo concentrations reacts strongly with a variety of clinically relevant drugs in vitro. Among these, hydrazine-containing and acylhydrazine-containing drugs (such as hydralazine and isoniazid) exhibit the strongest reactivity. Amine penicillin antibiotics cyclocillin and ampicillin, as well as cephalosporin antibiotics cephalexin, cefalexin, and Cephradine, also show significant reactivity. However, amine penicillic acid and cephalosporin antibiotics show almost no reactivity, suggesting that the acyl group of these antibiotics plays an important role in their reaction with acetaldehyde. The presence of groups that increase the electron density of the amine group appears to favor the reactivity of the molecule. Among several phenethylamine compounds tested, dopamine and norepinephrine showed the highest activity in forming adducts with acetaldehyde. In vitro studies have shown that the binding of acetaldehyde to the aforementioned drugs may lead to reduced bioavailability in vivo, and the possible adducts formed may mediate some side effects associated with concurrent drug use and alcohol consumption. For more complete data on interactions of Cephradine (9 drugs in total), please visit the HSDB record page.

[1]. Pharmacokinetics of cephradine administered intravenously and orally to young and elderly subjects. J Clin Pharmacol. 1990;30(10):893-899.

[2]. Intravenous use of cephradine and cefazolin against serious infections. Antimicrob Agents Chemother. 1979;15(1):119-122.

[3]. Cefradine blocks solar-ultraviolet induced skin inflammation through direct inhibition of T-LAK cell-originated protein kinase. Oncotarget. 2016;7(17):24633-24645.

[4]. In Vitro and In Vivo Antimicrobial Activity of Antibiotic-Conjugated Carriers with Rapid pH-Responsive Release Kinetics. Adv Healthc Mater. 2019;8(14):e1900247.

Cephradine is a first-generation cephalosporin antibiotic with a methyl substituent at the 3-position and a (2R)-2-amino-2-cyclohexyl-1,4-dien-1-ylacetamido substituent at the 7-position of its cephalosporin skeleton. It is an antibacterial drug belonging to the β-lactam class of cephalosporins. It is a semi-synthetic cephalosporin antibiotic. Anhydrous Cephradine is a cephalosporin antibacterial drug. Cephradine is a first-generation β-lactam cephalosporin antibiotic with bactericidal activity. Cephradine binds to and inactivates penicillin-binding protein (PBP) located on the inner membrane of the bacterial cell wall. PBP is involved in the final stages of bacterial cell wall assembly and cell wall remodeling during cell division. Inactivation of penicillin-binding protein (PBP) interferes with the cross-linking of peptidoglycan chains, which is crucial for maintaining the strength and rigidity of the bacterial cell wall. This leads to weakening of the bacterial cell wall, ultimately resulting in cell lysis.
Anhydrous Cephradine is the anhydrous form of Cephradine, a semi-synthetic, broad-spectrum, first-generation cephalosporin with antibacterial activity. Cephradine binds to and inactivates penicillin-binding proteins (PBPs) located on the inner membrane of bacterial cell walls. PBPs are enzymes involved in the final stage of bacterial cell wall assembly and in remodeling the cell wall during bacterial growth and division. Inactivation of PBPs interferes with the cross-linking of peptidoglycan chains, which is crucial for maintaining the strength and rigidity of bacterial cell walls. This leads to weakened bacterial cell walls and cell lysis.
A semi-synthetic cephalosporin antibiotic.

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Mechanism of Action
Cephradine is a first-generation cephalosporin antibiotic with an antibacterial spectrum similar to cephalexin. Like penicillin antibiotics, Cephradine belongs to the β-lactam class of antibiotics. It 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 subsequently mediated by bacterial cell wall autolysins (such as autolysins); Cephradine may interfere with autolysin inhibitors. Cephalosporins and cephamycins inhibit bacterial cell wall synthesis in a similar way to penicillins. Cephalosporins First-generation cephalosporins…are active against Gram-positive bacteria, with relatively weaker activity against Gram-negative bacteria. Cephalosporins

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Therapeutic Uses
Cephalosporins
Cephalosporins
Cephalosporins are indicated for the treatment of bacterial urinary tract infections caused by susceptible bacteria. (Included on the US product label)
Cephalosporins are indicated for the treatment of bacterial pharyngitis caused by susceptible bacteria. (Included on the US product label)
Cephalosporins are indicated for the treatment of skin and soft tissue infections caused by susceptible bacteria. /Included on the US product label/
For more complete data on the therapeutic uses of Cephradine (18 in total), please visit the HSDB record page.

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Drug Warnings
Patients with a history of gastrointestinal disease (especially colitis) should use cephalosporins with caution. Because there have been reports of antibiotic-associated pseudomembranous colitis caused by cephalosporin use, this possibility should be considered in the differential diagnosis of patients who develop diarrhea during or after cephalosporin use. /Cephalosporins/
Prolonged use of cephalosporins may lead to overgrowth of non-susceptible bacteria, especially Enterobacteriaceae, Pseudomonas, Enterococci, or Candida. If superinfection occurs, appropriate treatment should be administered. Cephalosporins
Other reported adverse reactions to cephalosporins include chest pain, pleural effusion, dyspnea or respiratory distress, cough, and rhinitis. Increased or decreased serum glucose levels have also been reported. The most common adverse reactions to cephalosporins are nausea, vomiting, and diarrhea. These reactions are usually mild and transient, but in rare cases may be severe enough to require discontinuation of the drug. Other possible gastrointestinal adverse reactions to oral cephalosporins include abdominal pain, tenesmus, upper abdominal pain/indigestion, decreased appetite/anorexia, glossitis, abdominal distension, candidiasis (e.g., oral thrush), altered taste, decreased salivation, and heartburn. Gastrointestinal adverse reactions may also occur with intramuscular or intravenous cephalosporins. /Cephalosporins/
For more complete data on drug warnings for Cephradine (9 in total), please visit the HSDB record page.

C16H19N3O4S

349.4

349.109

38821-53-3

Cephradine monohydrate;75975-70-1

38103

White to light yellow solid powder

1.5±0.1 g/cm3

693.1±55.0 °C at 760 mmHg

140-142ºC

373.0±31.5 °C

0.0±4.7 mmHg at 25°C

1.684

0.98

3

6

4

24

697

3

CC1=C(N2[C@@H]([C@@H](C2=O)NC(=O)[C@@H](C3=CCC=CC3)N)SC1)C(=O)O

RDLPVSKMFDYCOR-UEKVPHQBSA-N

InChI=1S/C16H19N3O4S/c1-8-7-24-15-11(14(21)19(15)12(8)16(22)23)18-13(20)10(17)9-5-3-2-4-6-9/h2-3,6,10-11,15H,4-5,7,17H2,1H3,(H,18,20)(H,22,23)/t10-,11-,15-/m1/s1

(6R,7R)-7-[[(2R)-2-amino-2-cyclohexa-1,4-dien-1-ylacetyl]amino]-3-methyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid

Anspor; Alpharma Brand of Cephradine; Cephradine

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

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

H2O : ~8.33 mg/mL (~23.84 mM)
DMSO : ≥ 3.6 mg/mL (~10.30 mM)

Solubility in Formulation 1: 4.55 mg/mL (13.02 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication (<60°C).

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