Gentamycin sulfate (solution for injection 4%)

Solutio Gentamycini sulfatis 4% pro injectionibus

 

International Non-proprietary Name

Gentamycin.

Gentamicin.

Pharmacotherapeutic group

Antibiotic of aminoglycosides class.

Composition

1 mL of the solution contains 40 mg of gentamycin sulfate.

Pharmacological action

Pharmacodynamics

Gentamycin sulfate is characterized by a wide range of antimicrobial activity. Is active against the majority of gram-negative and and grampositive microorganisms: Pseudomonas aeruginosa, Escherichia coli, Proteus spp., Klebsiella spp., Serratia spp., Salmonella spp., Shigella spp., Staphylococcus spp., including multiple resistant strains. Less active against streptococci of various strains and gram-negative cocci. The preparation is active against anaerobic bacteria, fungi, viruses.

Gentamycin sulfate exhibits bactericidal action.. Actively penetrating through bacterial cell membranes it binds with 30S subunit of bacterial ribosome and inhibits the synthesis of causative agent protein.

Pharmacokinetics

Maximum serum gentamicin concentration is achieved in 1 Hour after intramuscular injection. Following intravenous dropwise injection the antibiotic blood concentration within the first two hours exceeds the concentrations observed after intramuscular injection. Following both routes of injection the therapeutic concentrations of the preparation persist within 8 hours. Following endolymphatic administration gentamicin concentration in blood serum during the first 6 hours are similar to ones observed after intramuscular injection; therapeutic activity is kept for 12—24 hours. In patients with the impairment of renal secretory function blood concentration of the preparation is increased. As a rule following parenteral administration the preparation poorly penetrates through blood-brain barrier; during meningitis its concentrations in cerebro-spinial fluid is increased. The antibiotic in therapeutic concentrations is detected in kidneys, lungs, in exudate of pleural and peritoneal cavities. Crosses placenta. Not metabolized. Excreted via kidneys (70-95%), partially is excreted with bile.

Indications

Preparation is used for the treatment of sepsis, meningitis, peritonitis, bacterial endocarditis; infectious-inflammatory diseases of respiratory organs (pneumonitis, empyema, pulmonary abscess), infections of kidneys and urinary tracts; infected burns and other diseases, predominantly caused by gram-negative  microorganisms, resistant to antibiotics.

Gentamicin is intended for the treatment of pyogenic-septic diseases in patients with leukosis and malignant neoplasms in combination with cytostatic, radiotherapy and during immunosuppressants therapy. Endolymphatic route of injection is used in patients with severe course of a disease when other methods of treatment are ineffective.

Administration and dosing regimen

Gentamycin sulfate is administered intramuscularly, intravenously (dropwise), endolymphatically. Maximum daily dose for adults and children by intramuscular and intravenous injection is 5 mg/kg, when administered endolymphatically - 2 mg/kg. Single dose for adults and children above 14 years with infections of urinary tracts is 0.4 mg/kg, daily dose is 0.8-1.2 mg/kg. In severe course of infection the daily dose can be increased up to 3 mg/kg. In sepsis and other severe infections (peritonitis, necrotizing pneumonia, lungs abscess and others) depending on the severity of the process the single dose for adults and children above 14 years is 0.8-1 mg/kg, daily - 2.4-3.2 mg/kg. For younger children, especially during the first weeks of life, gentamicin is recommended only in life-threatening states (sepsis, septic endocarditis, meningitis, peritonitis). The daily dose of gentamycin sulfate for newborn and infants is 2-5 mg/kg; for children of 1-5 years — 1.5-3 mg/kg; 6-14 years - 3 mg/kg. Should be divided into 2-3 administrations.

When administered intravenously to adults the single dose of the preparation is diluted with 200 mL (for children in
50—100 mL) of 5% glucose solution or sodium chloride isotonic solution. The preparation is administered 2 time a day at a rate of 60 drops per minute. The concentration of the preparation in the solution should not exceed 1 mg/mL.

In case of renal impairment the scheme of injection is adjusted by the reduction of doses or the prolongation of intervals between injections. During hemodialysis an additional dose of antibiotic should be administered.

The duration of the treatment in case of intramuscular injection id 7-10 days, in case of intravenous injection is 2-3 days with subsequent transfer to intramuscular injection.

Endolymphatically the preparation is slowly (at a rate of 0.5-1 mL per min) injected into peripheral lymphatic vessels on the foot or in lower third of the anticnemion 1-2 times daily with the interval of not less than 12 hours. The course of treatment consists of 3-8 injections within 5-10 days.

Side effects

During the therapy with the preparation impairment of hearing and balance, kidneys damage, headache, nausea, vomiting, convulsions, muscular weakness, change of blood cell composition (anaemia, leucopenia, thrombocythopenia, granulocytopenia), increase of hepatic transaminase activity, hyperbilirubinemia, allergic reactions (cutaneous pruritus, hives) can occur.

When administered endolymphatically gentamicin can cause a tingling sensation along the lymphatic vessel within the first minute which is usually quickly resolved.

Contraindications

Administration of gentamicin is contraindicated in allergy to the preparation. Gentamicin should not be used in severe impairment of renal function, uraemia, in hearing and vestibular organ disease, connected with neuritis of 8th pair of cranial nerve, myasthenia, during lactation (the preparation should be withdrawn during treatment period), during pregnancy, in case benefits outweigh the risks. Preparation should not be used concomitantly or immediately after the administration of other oto- and nephrotoxic preparations, as well as with loop diuretics. Endolymphatically gentamycin sulfate should not be used during diseases accompanied by the impairment of lymph efflux (lymphedema, lymphostasis, congenial or acquired lymphosclerosis), in presence of ulcers, wound or inflammatory surfaces at the site of injection into lymphatic vessel.

Precautions

Gentamicin should be used with caution during parkinsonism, myasthenia, impairment of renal function.

Drug interactions

When used concomitantly with aminoglycosides, vancomycin, cephalosporins, ethacrynic acid oto- and nephrotoxic effects can be enhanced. It increases (mutually) the effect of carbenicillin, benzylpenicillins and cephalosporins. When used concomitantly with indomethacin, loop diuretics (including furosemide), gentamicin plasma concentrations are increased, as well as the risk of the appearance of side effects. Neuromuscular relaxants increase the possibility of respiratory paralysis. When used concomitantly with agents for inhalation anaesthesia, opoid analgesic the risk of the development of neuromuscular blockade including apnoea can be increased.

Presentation

4% solution in ampoules of 2 ml.