Ceftriaxone Sodium

CEFTRIAXONE SODIUM- ceftriaxone sodium injection, powder, for solution
A-S Medication Solutions

To reduce the development of drug-resistant bacteria and maintain the effectiveness of ceftriaxone for injection, and other antibacterial drugs, ceftriaxone for injection should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.

DESCRIPTION

Ceftriaxone for injection, USP is a sterile, semisynthetic, broad-spectrum cephalosporin antibiotic for intravenous or intramuscular administration. Ceftriaxone sodium is (6R , 7R)-7-[2-(2-Amino-4-thiazolyl) glyoxylamido]-8-oxo-3-[[(1,2,5,6-tetrahydro-2-methyl-5,6-dioxo-as -triazin-3-yl)thio]methyl]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid, 72 -(Z)-(O -methyloxime), disodium salt, sesquaterhydrate.

The chemical formula of ceftriaxone sodium is C18 H16 N8 Na2 O7 S3 •3.5H2 O. It has a calculated molecular weight of 661.60 and the following structural formula:

chemical-structure
(click image for full-size original)

Ceftriaxone sodium is a white to yellowish crystalline powder which is readily soluble in water, sparingly soluble in methanol and very slightly soluble in ethanol. The pH of a 1% aqueous solution is approximately 6.7. The color of ceftriaxone sodium solutions ranges from light yellow to amber, depending on the length of storage, concentration and diluent used. Each vial contains ceftriaxone sodium equivalent to 250 mg, 500 mg, 1 gram or 2 grams of ceftriaxone activity. Ceftriaxone sodium contains approximately 83 mg (3.6 mEq) of sodium per gram of ceftriaxone activity.

CLINICAL PHARMACOLOGY

Average plasma concentrations of ceftriaxone following a single 30-minute intravenous (IV) infusion of a 0.5, 1 or 2 g dose and intramuscular (IM) administration of a single 0.5 (250 mg/mL or 350 mg/mL concentrations) or 1 g dose in healthy subjects are presented in Table 1.

Table 1. Ceftriaxone Plasma Concentrations after Single Dose Administration
Average Plasma Concentrations (mcg/mL)
Dose/Route 0.5 hour 1 hour 2 hour 4 hour 6 hour 8 hour 12 hour 16 hour 24 hour

0.5 g IV*

82

59

48

37

29

23

15

10

5

0.5 g IM

250 mg/mL

22

33

38

35

30

26

16

ND

5

0.5 g IM

350 mg/mL

20

32

38

34

31

24

16

ND

5

1 g IV*

151

111

88

67

53

43

28

18

9

1 g IM

40

68

76

68

56

44

29

ND

ND

2 g lV*

257

192

154

117

89

74

46

31

15

ND = Not determined.

* IV doses were infused at a constant rate over 30 minutes.

Ceftriaxone was completely absorbed following IM administration with mean maximum plasma concentrations occurring between 2 and 3 hours post-dose. Multiple IV or IM doses ranging from 0.5 to 2 g at 12 to 24 hour intervals resulted in 15% to 36% accumulation of ceftriaxone above single dose values.

Ceftriaxone concentrations in urine are shown in Table 2.

Table 2. Urinary Concentrations of Ceftriaxone after Single Dose Administration
Dose/Route Average Urinary Concentrations (mcg/mL)
0 to 2 hour 2 to 4 hour 4 to 8 hour 8 to 12 hour 12 to 24 hour 24 to 48 hour

0.5 g IV

526

366

142

87

70

15

0.5 g IM

115

425

308

127

96

28

1 g IV

995

855

293

147

132

32

1 g IM

504

628

418

237

ND

ND

2 g IV

2692

1976

757

274

198

40

ND = Not determined.

Thirty-three percent to 67% of a ceftriaxone dose was excreted in the urine as unchanged drug and the remainder was secreted in the bile and ultimately found in the feces as microbiologically inactive compounds. After a 1 g IV dose, average concentrations of ceftriaxone, determined from 1 to 3 hours after dosing, were 581 mcg/mL in the gallbladder bile, 788 mcg/mL in the common duct bile, 898 mcg/mL in the cystic duct bile, 78.2 mcg/g in the gallbladder wall and 62.1 mcg/mL in the concurrent plasma.

Over a 0.15 to 3 g dose range in healthy adult subjects, the values of elimination half-life ranged from 5.8 to 8.7 hours; apparent volume of distribution from 5.78 to 13.5 L; plasma clearance from 0.58 to 1.45 L/hour; and renal clearance from 0.32 to 0.73 L/hour. Ceftriaxone is reversibly bound to human plasma proteins, and the binding decreased from a value of 95% bound at plasma concentrations of < 25 mcg/mL to a value of 85% bound at 300 mcg/mL. Ceftriaxone crosses the blood placenta barrier.

The average values of maximum plasma concentration, elimination half-life, plasma clearance and volume of distribution after a 50 mg/kg IV dose and after a 75 mg/kg IV dose in pediatric patients suffering from bacterial meningitis are shown in Table 3. Ceftriaxone penetrated the inflamed meninges of infants and pediatric patients; CSF concentrations after a 50 mg/kg IV dose and after a 75 mg/kg IV dose are also shown in Table 3.

Table 3. Average Pharmacokinetic Parameters of Ceftriaxone in Pediatric Patients with Meningitis
50 mg/kg IV 75 mg/kg IV

Maximum Plasma

Concentrations (mcg/mL)

216

275

Elimination Half-life (hour)

4.6

4.3

Plasma Clearance (mL/hour/kg)

49

60

Volume of Distribution (mL/kg)

338

373

CSF Concentration –

inflamed meninges (mcg/mL)

5.6

6.4

Range (mcg/mL)

1.3 to 18.5

1.3 to 44

Time after dose (hour)

3.7 (± 1.6)

3.3 (± 1.4)

Compared to that in healthy adult subjects, the pharmacokinetics of ceftriaxone were only minimally altered in elderly subjects and in patients with renal impairment or hepatic dysfunction (Table 4); therefore, dosage adjustments are not necessary for these patients with ceftriaxone dosages up to 2 g per day. Ceftriaxone was not removed to any significant extent from the plasma by hemodialysis; in six of 26 dialysis patients, the elimination rate of ceftriaxone was markedly reduced.

Table 4. Average Pharmacokinetic Parameters of Ceftriaxone in Humans
Subject Group Elimination Half-Life (hour) Plasma Clearance (L/hour) Volume of Distribution (L)

Healthy Subjects

5.8 to 8.7

0.58 to 1.45

5.8 to 13.5

Elderly Subjects

(mean age, 70.5 year)

8.9

0.83

10.7

Patients With

Renal Impairment

Hemodialysis Patients

(0 to 5 mL/min) *

14.7

0.65

13.7

Severe (5 to 15 mL/min)

15.7

0.56

12.5

Moderate (16 to 30 mL/min)

11.4

0.72

11.8

Mild (31 to 60 mL/min)

12.4

0.70

13.3

Patients With

Liver Disease

8.8

1.1

13.6

* Creatinine clearance.

The elimination of ceftriaxone is not altered when ceftriaxone is co-administered with probenecid.

All MedLibrary.org resources are included in as near-original form as possible, meaning that the information from the original provider has been rendered here with only typographical or stylistic modifications and not with any substantive alterations of content, meaning or intent.

This site is provided for educational and informational purposes only, in accordance with our Terms of Use, and is not intended as a substitute for the advice of a medical doctor, nurse, nurse practitioner or other qualified health professional.

Privacy Policy | Copyright © 2021. All Rights Reserved.