Ototoxicity streptomycin

Stiepton dn was isolated by Waksman in 1944, and its activity against M tuberculosis ensured its use as a primaiy ding in the treatment of tuberculosis. Unfortunately, its ototoxicity and the rapid development of resistance have tended to modify its usefulness, and although it still remains a front-hne dmg against tuberculosis it is usually used in combination with isoniazid and p(4)-aminosalicyhc acid (section 11.5). Streptomycin also shows activity against other types of bacteria,... 

Streptomycin Adults See footnote8 Children 20-40 mg/kg per day Ototoxicity, neurotoxicity, nephrotoxicity Baseline audiogram, vestibular testing, Romber testing and SCr Monthly assessments of renal function and auditory or vestibular symptoms... 

Previous reactions to these agents. With the exception of the use of streptomycin in tuberculosis, these agents generally are not indicated in long-term therapy because of the ototoxic and nephrotoxic hazards of extended administration. 

Ototoxicity Vestibular and auditory dysfunction can follow the administration of streptomycin. The degree of impairment is directly proportional to the dose and duration of streptomycin administration, the age of the patient, the leyel of renal function, and the amount of underlying existing auditory dysfunction. 

The ototoxic effects of streptomycin are potentiated by the coadministration of ethacrynic acid, furosemide, mannitol, and possibly other diuretics. 

Aminoglycosides accumulate in otolymph and can cause both vestibular and auditory ototoxicity, both of which can be irreversible. Uptake is driven by the concentration gradient between blood and the otolymph this process is saturable. Sustained high concentrations in otolymph first destroy hair cells that are sensitive to high-frequency sounds. Streptomycin is more likely to cause vestibular toxicity than ototoxicity. The severity... 

Ototoxicity and nephrotoxicity are the major concerns during administration of streptomycin and other aminoglycosides. The toxic effects are dose related and increase with age and underlying renal insufficiency. All aminoglycosides require dose adjustment in renal failure patients. Ototoxicity is severe when aminoglycosides are combined with other potentially ototoxic agents. 

Thiacetazone is active against many strains of M. tuberculosis. It is not marketed in the United States. However, because of its low cost, it is used as a first-line agent in East Africa, especially in combination with compounds such as isoniazid. The most common side effects of thiacetazone include GI intolerance and development of rashes. It causes significant ototoxicity, especially when coadministered with streptomycin. Life-threatening hypersensitivity reactions, such as hepatitis, transient marrow aplastic syndromes, neutropenia, and thrombocytopenia, have been reported. 

Streptomycin is ototoxic and nephrotoxic. Vertigo and hearing loss are the most common adverse effects and may be permanent. Toxicity is dose-related, and the risk is increased in the elderly. As with all aminoglycosides, the dose must be adjusted according to renal function (see Chapter 45). Toxicity can be reduced by limiting therapy to no more than 6 months whenever possible. 

Streptomycin Prevents bacterial protein synthesis by binding to the S12 ribosomal subunit (see also Chapter 45) Bactericidal activity against susceptible mycobacteria Used in tuberculosis when an injectable drug is needed or desirable and in treatment of drug-resistant strains IM, IV renal clearance (half-life 2.5 h) administered daily initially, then 2 x week Toxicity Nephrotoxicity, ototoxicity... 

Streptomycin is given intramuscularly. It exerts its effects only on extracellular tubercle bacilli. When combined with other drugs, it delays the emergence of streptomycin-resistant mutants. It is ototoxic and may cause deafness. 

Rifampicin can cause renal failure, transient disturbances of liver function tests, hyperbilirubinaemia or severe hepatotoxicity and other side-effects. Streptomycin can cause renal and ototoxicity. The combination of rifampicin and streptomycin increases the risk of streptomycin-induced renal failure. 

PLATINUM COMPOUNDS AMINOGLYCOSIDES, CAPREOMYCIN, COLISTIN, STREPTOMYCIN, VANCOMYCIN t risk of renal toxicity and renal failure and of ototoxicity. The ototoxicity tends to occur when cisplatin is administered early during the course of aminoglycoside therapy Additive renal toxicity Monitor renal function prior to and during therapy, and ensure an intake of at least 2 L of fluid daily. Monitor serum potassium and magnesium and correct any deficiencies. Most side-effects of aminoglycosides are dose-related, and it is necessary to t interval between doses and 1 dose of aminoglycoside if there is impaired renal function... 

The same spectrum of toxicity (ototoxicity and nephrotoxicity) is shared by all members of the group, The more important and frequent interactions are pharmacodynamic. Streptomycin and gentamicin produce predominantly vestibular effects, whereas amikacin, kanamycin and neomycin primarily affect auditory function. All are rapidly excreted by the kidney,... 

In a quantitative assessment of vestibular hair cells and Scarpa s ganglion cells in 17 temporal bones from 10 individuals with aminoglycoside ototoxicity, streptomycin caused a significant loss of both type I and type II hair cells in all five vestibular sense organs (19). The vestibular ototoxic effects of kanamycin appeared to be similar to those of streptomycin, whereas neomycin did not cause loss of vestibular hair cells. There was no significant loss of Scarpa s ganglion cells. 

Capreomycin should never be combined with streptomycin or other aminoglycosides because of nephrotoxicity and ototoxicity (3). 

Dihydrostreptomycin was developed as a non-ototoxic alternative to streptomycin, however it was just as ototoxic. Clinically, dihydrostreptomycin used to be given in combination with penicillin G, but most of these injectable products are no longer available. 

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