Streptomycin

WARNING THE RISK OF SEVERE NEUROTOXIC REACTIONS IS SHARPLY INCREASED IN PATIENTS WITH IMPAIRED RENAL FUNCTION OR PRE-RENAL AZOTEMIA. THESE INCLUDE DISTURBANCES OF VESTIBULAR AND COCHLEAR FUNCTION, OPTIC NERVE DYSFUNCTION, PERIPHERAL NEURITIS, ARACHNOIDITIS, AND ENCEPHALOPATHY MAY ALSO OCCUR. THE INCIDENCE OF CLINICALLY DETECTABLE, IRREVERSIBLE VESTIBULAR DAMAGE IS PARTICULARLY HIGH IN PATIENTS TREATED WITH STREPTOMYCIN. RENAL FUNCTION SHOULD BE MONITORED CAREFULLY; PATIENTS WITH RENAL IMPAIRMENT AND/OR NITROGEN RETENTION SHOULD RECEIVE REDUCED DOSES. THE PEAK SERUM CONCENTRATION IN INDIVIDUALS WITH KIDNEY DAMAGE SHOULD NOT EXCEED 20 TO 25 MCG/ML. THE CONCURRENT OR SEQUENTIAL USE OF OTHER NEUROTOXIC AND/OR NEPHROTOXIC DRUGS WITH STREPTOMYCIN SULFATE, INCLUDING NEOMYCIN, KANAMYCIN, GENTAMICIN, CEPHALORIDINE, PAROMOMYCIN, VIOMYCIN, POLYMYXIN B, COLISTIN, TOBRAMYCIN AND CYCLOSPORINE SHOULD BE AVOIDED. THE NEUROTOXICITY OF STREPTOMYCIN CAN RESULT IN RESPIRATORY PARALYSIS FROM NEUROMUSCULAR BLOCKAGE, ESPECIALLY WHEN THE DRUG IS GIVEN SOON AFTER THE USE OF ANESTHESIA OR MUSCLE RELAXANTS. THE ADMINISTRATION OF STREPTOMYCIN IN PARENTERAL FORM SHOULD BE RESERVED FOR PATIENTS WHERE ADEQUATE LABORATORY AND AUDIOMETRIC TESTING FACILITIES ARE AVAILABLE DURING THERAPY.

WARNINGS Ototoxicity Both 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, to the age of the patient, to the level of renal function and to the amount of underlying existing auditory dysfunction. The ototoxic effects of the aminoglycosides, including streptomycin, are potentiated by the co-administration of ethacrynic acid, mannitol, furosemide and possibly other diuretics. The vestibulotoxic potential of streptomycin exceeds that of its capacity for cochlear toxicity. Vestibular damage is heralded by headache, nausea, vomiting and disequilibrium. Early cochlear injury is demonstrated by the loss of high frequency hearing. Appropriate monitoring and early discontinuation of the drug may permit recovery prior to irreversible damage to the sensorineural cells. Pregnancy Streptomycin can cause fetal harm when administered to a pregnant woman. Because streptomycin readily crosses the placental barrier, caution in use of the drug is important to prevent ototoxicity in the fetus. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the fetus. Clostridium difficile associated diarrhea Clostridium difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including Streptomycin for Injection, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile. C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile, and surgical evaluation should be instituted as clinically indicated. Risk of Ototoxicity Due to Mitochondrial DNA Variants Cases of ototoxicity with aminoglycosides have been observed in patients with certain variants in the mitochondrially encoded 12S rRNA gene ( MT-RNR1 ), particularly the m.1555A>G variant. Ototoxicity occurred in some patients even when their aminoglycoside serum levels were within the recommended range. Mitochondrial DNA variants are present in less than 1% of the general US population, and the proportion of the variant carriers who may develop ototoxicity as well as the severity of ototoxicity is unknown. In case of known maternal history of ototoxicity due to aminoglycoside use or a known mitochondrial DNA variant in the patient, consider alternative treatments other than aminoglycosides unless the increased risk of permanent hearing loss is outweighed by the severity of infection and lack of safe and effective alternative therapies.

ADVERSE REACTIONS The following reactions are common: vestibular ototoxicity (nausea, vomiting, and vertigo); paresthesia of face; rash; fever; urticaria; angioneurotic edema; and eosinophilia. The following reactions are less frequent: cochlear ototoxicity (deafness); exfoliative dermatitis; anaphylaxis; azotemia; leucopenia; thrombocytopenia; pancytopenia; hemolytic anemia; muscular weakness; and amblyopia. Vestibular dysfunction resulting from the parenteral administration of streptomycin is cumulatively related to the total daily dose. When 1.8 to 2 g/day are given, symptoms are likely to develop in the large percentage of patients - especially in the elderly or patients with impaired renal function - within four weeks. Therefore, it is recommended that caloric and audiometric tests be done prior to, during, and following intensive therapy with streptomycin in order to facilitate detection of any vestibular dysfunction and/or impairment of hearing which may occur. Vestibular symptoms generally appear early and usually are reversible with early detection and cessation of streptomycin administration. Two to three months after stopping the drug, gross vestibular symptoms usually disappear, except from the relative inability to walk in total darkness or on very rough terrain. Although streptomycin is the least nephrotoxic of the aminoglycosides, nephrotoxicity does occur rarely. Clinical judgment as to termination of therapy must be exercised when side effects occur. For medical advice about adverse reactions, contact your medical professional. To report SUSPECTED ADVERSE REACTIONS, contact XGen Pharmaceuticals DJB, Inc. at 1-866-390-4411 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.