Mycin

Gentamicin sulfate.

Pharmacology: Gentamicin is a bactericidal antibiotic that acts by inhibiting normal protein synthesis in susceptible micro-organisms. It is active against a wide variety of pathogens including Escherichia coli, Proteus species, Pseudomonas aeruginosa, Klebsiella-Enterobacter-Serratia group, Citrobacter species, Staphylococcus species, Streptococcus pneumoniae, Salmonella and Shigella species.

Gentamicin Sulfate Injection is indicated for the treatment of serious urinary tract infections, bacteremia, meningitis, cerebral ventriculitis, infected burns, osteomyelitis, pneumonia, peritonitis, and otitis caused by suspected gram-negative bacteria.
Gentamicin Sulfate Injection is also indicated for the treatment of serious infections caused by susceptible strains of Pseudomonas aeruginosa, Proteus species (indole-positive and indole-negative). Escherichia coli, Klebsiella-Enterobacter-Serratia species, Citrobacter species and Staphyloccus species (coagulase-positive and coagulase-negative).
Gentamicin has been used effectively in combination with carbenicillin for the treatment of life threatening infections caused by Pseudomonas aeruginosa. It has also been found to be effective, when used in conjunction with penicillin type drugs for the treatment of endocarditis caused by Group D Streptococci.

Gentamicin Sulfate Injection may be given intramuscularly or intravenously. The patient's pretreatment body weight (lean body mass in case of obese patients) should be used for calculation of correct dosage. The following is recommended as a dosage guide in patients with normal renal function.
Adults: 1 to 1.7 mg/kg every 8 hours.
Children: 2.0 to 2.5 mg/kg every 8 hours.
Infants and neonates: 2.5 mg/kg every 8 hours.
Premature or full term neonates one week of age or less: 2.5 mg/kg every 12 hours.
The dosage for patients with compromised renal function undergoing hemodialysis, depends on the amount of drug removed from the blood. The amount of drug may be reduced by as much as 50% following an eight-hour dialysis. At the end of the dialysis period a dose of 1 to 1.7 mg/kg in adults and 2 mg/kg in children may be administered depending on the severity of the infection.

In the event of overdosage or toxic reactions, hemodialysis may aid in the removal of gentamicin from the blood and is especially important if the renal function is or becomes comprised.

Hypersensitivity to Gentamicin is a contraindication to its use. A history of hypersensitivity or serious toxic reactions to other aminoglycosides may contraindicate the use of gentamicin because of the known cross sensitivity of patients to drugs in this class.

Gentamicin sulfate 40 mg/mL inj. contains sodium metabisulfite 0.32%, a sulfite that may cause serious allergic type reactions including anaphylactic symptoms and life threatening or less severe asthmatic episodes in certain susceptible people. The overall prevalence of sulfite toxicity in the general population is unknown and probably low. Sulfite sensitivity is been more in asthmatic than in non-asthmatic people. Patients treated with aminoglycosides should be under close clinical observation because of the potential toxicity associated with their use. Nephrotoxicity, manifested by ototoxicity, both vestibular and auditory, can occur particularly in patients with existing renal damage. Renal and eighth cranial nerve function should be closely monitored. Urine should be examined for decreased specific gravity, increased excretion of protein and presence of cells or casts. BUN, serum creatinine or creatinine clearance should be monitored. Evidence of ototoxicity requires dosage adjustment or discontinuation of use for the drug. Serum concentrations should be monitored and the dosage adjusted so that prolonged levels above 12 mcg/mL are avoided. In the event of overdosage or toxic reactions, hemodialysis may aid in removal of the drug. Concurrent and/or sequential use of potentially neurotoxic/nephrotoxic drugs such as cisplatin, cephaloridine, kanamycin, amikacin, neomycin, polymixin B, colistin, paromomycin, streptomycin, tobramycin, vancomycin and viomycin should be avoided. Concurrent use with potent diuretics such as furosemide and ethacrynic acid should be avoided. When administered intravenously, diuretics may enhance aminoglycoside toxicity by altering the antibiotic concentration in serum and tissue.
Aminoglycosides can cause fetal harm when administered to a pregnant woman. Animal reproduction studies conducted on rats and rabbits did not reveal evidence of impaired fertility or harm to the fetus due to gentamicin sulfate. It is not known whether gentamicin sulfate can cause fetal harm when administered to a pregnant woman or can effect reproduction capacity. If gentamicin is used during pregnancy or if the patient becomes pregnant while taking gentamicin, she should be aprised of the potential hazard to the fetus.

Neurotoxic and nephrotoxic antibiotics may be absorbed in significant quantities from the body surface after local irrigation or application. Increased nephrotoxicity has been reported following concomitant administration of aminoglycoside antibiotics and cephalosporins. Neuromuscular blockade and respiratory paralysis may possibly occur in patients receiving anaesthetics, or neuromuscular blocking agents such as succinylcholine, tubocurarine or decamethonium, or in patients receiving massive transfusions of citrate anticoagulated blood. If neuromuscular blockade occurs, calcium salts may reverse it.
Aminoglycosides should be used with caution in patients with neuromuscular disorders such as myasthenia gravis, since these drugs may aggravate muscle weakness. Appropriate corrective therapy (electrolyte administration) should be employed if there is any evidence of hypomagnesia and hypokalemia.
Use in Pregnancy: Safety for use in pregnancy has not been established.

Safety for use in pregnancy has not been established.

Adverse nephrotoxic (renal) effects, as demonstrated by the presence of casts, cells or protein in the urine or by rising BUN, NPN, serum creatinine and oliguria have been reported particularly in patients with renal impairment and those treated with larger doses and for longer periods than recommended. Neurotoxicity manifested by adverse effects on both vestibular and auditory branches of the eighth cranial nerves has been reported, primarily in patients, with renal impairment and those treated with large doses and for longer periods than recommended. Symptoms include dizziness, tinnitus, vertigo, roaring in the ears and hearing loss, which, as with other aminoglycosides may be irreversible. Other factors contributing to increased toxicity may include excessive dosage, dehydration and exposure to other ototoxic drugs. Peripheral neuropathy or encephalopathies, including numbness, skin tingling, muscle twitching, convulsions and a myasthenia gravis-like syndrome have been reported.
Other reported adverse reactions include respiratory depression, lethargy, confusion, depression, visual disturbances, decreased appetite, weight loss, hypotension, and hypertension, rash, itching, urticaria, generalized burning, laryngeal edema, anaphylactoid reactions, fever, headache, nausea, vomiting, increased salivation, stomatitis, purpura, pseudotumor cerebri, acute organic brain syndrome, pulmonary fibrosis, alopecia, joint pain, transient hepatomegaly and splenomegaly.

Concurrent and/or sequential systemic or topical use of other potentially neurotoxic and/or nephrotoxic drugs should be avoided. The concurrent use of gentamicin with potent diuretics should be avoided, since certain diuretics themselves may cause ototoxicity. A reduction in gentamicin serum half life has been reported in patients with severe renal impairment receiving carbenicillin concomitantly with Gentamicin. Appropriate therapy is indicated if treatment with Gentamicin results in severe growth of nonsusceptible microorganisms.

Store at temperature not exceeding 30°C.
Shelf-Life: 24 months.

Aminoglycosides

J01GB03 - gentamicin ; Belongs to the class of other aminoglycosides. Used in the systemic treatment of infections.

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