KANAMYCIN

Absorption

Kanamycin is rapidly absorbed after intramuscular injection and peak serum levels are generally reached within approximately one hour. Poor oral and topical absorption except with severe skin damage.

Toxicity

Mild and reversible nephrotoxicity may be observed in 5 - 25% of patients. Amikacin accumulates in proximal renal tubular cells. Tubular cell regeneration occurs despite continued drug exposure. Toxicity usually occurs several days following initiation of therapy. May cause irreversible ototoxicity. Otoxocity appears to be correlated to cumulative lifetime exposure. Drug accumulation in the endolymph and perilymph of the inner ear causes irreversible damage to hair cells of the cochlea or summit of ampullar cristae in the vestibular complex. High frequency hearing is lost first with progression leading to loss of low frequency hearing. Further toxicity may lead to retrograde degeneration of the 8th cranial (vestibulocochlear) nerve. Vestibular toxicity may cause vertigo, nausea, vomiting, dizziness and loss of balance. Oral LD50 is 17500 mg/kg in mice, over 4 g/kg in rats, and over 3 g/kg in rabbits.

The Uses of KANAMYCIN

Kanamycin A is an antibiotic complex produced by Streptomyces kanamyceticus Okami & Umezawa from Japanese soil. Comprised of three components, kanamycin A, the major component, and kanamycins B and C, two minor congeners. Antibacterial.

The Uses of KANAMYCIN

Antibacterial Kantrex (Apothecon).

Indications

Kanamycin, O-3-amino-3-deoxy-α-D-glucopyranosyl-(1→6)-O-[6-deoxy- 6-amino-α-D-glucopyranosyl-(1→4)]–2-deoxy-D-streptamine (32.4.6), is isolated from a culture fluid of the actinomycete Streptomyces kanamyceticus, which produces three antibiotics—kanamycins A, B, and C.
Kanamycin A is similar to streptomycin and neomycines, and it possesses a broad spectrum of antimicrobial action. It is active with respect to most Gram-positive and Gramnegative microorganisms (staphylococci, colon bacillus, klebisella, Fridlender’s bacillus, proteus, shigella, salmonella).
It is used to treat sepsis, meningitis, osteomyelitis, peritonitis, pneumonia, pyelonephritis, pyelocystitis, infected wounds, and post-operational, purulent complications that are caused by microorganisms sensitive to this drug. Kanamycin is used to treat tuberculosis of the lungs and other organs upon resistance to other antituberculosis drugs. Synonyms of this drug are karmycin, kamaxin, resistomycin, and many others.

Definition

ChEBI: Kanamycin A is a member of kanamycins. It has a role as a bacterial metabolite. It is a conjugate base of a kanamycin A(4+).

Background

Kanamycin (also known as kanamycin A) is an aminoglycoside bacteriocidal antibiotic, available in oral, intravenous, and intramuscular forms, and used to treat a wide variety of infections. Kanamycin is isolated from the bacterium Streptomyces kanamyceticus and its most commonly used form is kanamycin sulfate.

Indications

For treatment of infections where one or more of the following are the known or suspected pathogens: E. coli, Proteus species (both indole-positive and indole-negative), E. aerogenes, K. pneumoniae, S. marcescens, and Acinetobacter species.

brand name

Klebcil (King).

Antimicrobial activity

It is active against staphylococci, including methicillin-resistant strains. Other aerobic and anaerobic Gram-positive cocci and most Gram-positive rods are resistant, but M. tuberculosis is susceptible. It is widely active against most aerobic Gram-negative rods, except Burkholderia cepacia and Sten. maltophilia. Treponema pallidum, Leptospira and Mycoplasma spp. are all resistant.

Acquired resistance

Resistance is usually plasmid borne and due to enzymatic inactivation of the drug by enzymes that also inactivate gentamicin or tobramycin . Resistance due to reduced permeability is also encountered.

Pharmacokinetics

C_max 500 mg intramuscular： c.15–20 mg/L after 1 h
Plasma half-life: 2.5 h
Volume of distribution: 0.3 L/kg
Plasma protein binding: Low
Absorption and distribution
Very little is absorbed from the intestinal tract. The peak plasma concentration in the neonate is dose related: concentrations of 8–30 mg/L (mean 18 mg/L) have been found 1 h after a 10 mg/kg dose. The drug is confined to the extracellular fluid. The concentration in serous fluids is said to equal that in the plasma, but it does not enter the CSF in therapeutically useful concentrations even in the presence of meningeal inflammation.
Excretion
It is excreted almost entirely by the kidneys, almost exclusively in the glomerular filtrate. Up to 80% of the dose appears unchanged in the urine over the first 24 h, producing concentrations around 100–500 mg/L. It is retained in proportion to reduction in renal function. Less than 1% of the dose appears in the bile. In patients receiving 500 mg intramuscularly preoperatively, concentrations of 2–23 mg/L have been found in bile and 8–14 mg/kg in gallbladder wall.

Pharmacokinetics

Kanamycin is an aminoglycoside antibiotic. Aminoglycosides work by binding to the bacterial 30S ribosomal subunit, causing misreading of t-RNA, leaving the bacterium unable to synthesize proteins vital to its growth. Aminoglycosides are useful primarily in infections involving aerobic, Gram-negative bacteria, such as Pseudomonas, Acinetobacter, and Enterobacter. In addition, some mycobacteria, including the bacteria that cause tuberculosis, are susceptible to aminoglycosides. Infections caused by Gram-positive bacteria can also be treated with aminoglycosides, but other types of antibiotics are more potent and less damaging to the host. In the past the aminoglycosides have been used in conjunction with penicillin-related antibiotics in streptococcal infections for their synergistic effects, particularly in endocarditis. Aminoglycosides are mostly ineffective against anaerobic bacteria, fungi and viruses.

Clinical Use

Formerly used for severe infection with susceptible organisms, it has largely been superseded by other aminoglycosides.

Side Effects

Intramuscular injections are moderately painful, and minor side effects similar to those encountered with streptomycin have been described. Eosinophilia in the absence of other manifestations of allergy occurs in up to 10% of patients. Other manifestations of hypersensitivity are rare.
As with other aminoglycosides, the most important toxic effects are on the eighth nerve and much less frequently on the kidney. Renal damage is seen principally in patients with pre-existing renal disease or treated concurrently or sequentially with other potentially nephrotoxic agents. The drug accumulates in the renal cortex, producing cloudy swelling, which may progress to acute necrosis of proximal tubular cells with oliguric renal failure. Less dramatic deterioration of renal function, particularly exaggeration of the potential nephrotoxicity of other drugs or of existing renal disease, is of principal importance because it increases the likelihood of ototoxicity.
Vestibular damage is uncommon but may be severe and prolonged. Hearing damage is usually bilateral, and typically affects frequencies above the conversational range. Acute toxicity is most likely in patients in whom the plasma concentration exceeds 30 mg/L, but chronic toxicity may be seen in patients treated with the drug over long periods. Auditory toxicity may be potentiated by concurrent treatment with potent diuretics like ethacrynic acid. If tinnitus – which usually heralds the onset of auditory injury – develops, the drug should be withdrawn.
Neuromuscular blockade is seen particularly in patients receiving other muscle relaxants or suffering from myasthenia gravis and may be reversed by neostigmine.

Metabolism

Not Available