Lincomycin

INDICATIONS AND USAGE Lincomycin Injection sterile solution is indicated in the treatment of serious infections due to susceptible strains of streptococci, pneumococci, and staphylococci. Its use should be reserved for penicillin-allergic patients or other patients for whom, in the judgment of the physician, a penicillin is inappropriate. Because of the risk of CDAD, as described in the BOXED WARNING , before selecting lincomycin the physician should consider the nature of the infection and the suitability of other alternatives. Indicated surgical procedures should be performed in conjunction with antibacterial therapy. Lincomycin Injection may be administered concomitantly with other antimicrobial agents when indicated. Lincomycin Injection is not indicated in the treatment of minor bacterial infections or viral infections. To reduce the development of drug-resistant bacteria and maintain the effectiveness of lincomycin injection and other antibacterial drugs, lincomycin injection should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.

DOSAGE AND ADMINISTRATION If significant diarrhea occurs during therapy, lincomycin injection should be discontinued. (see BOXED WARNING ) INTRAMUSCULAR— Adults: Serious infections —600 mg (2 mL) intramuscularly every 24 hours. More severe infections —600 mg (2 mL) intramuscularly every 12 hours or more often. Pediatric patients over 1 month of age: Serious infections —one intramuscular injection of 10 mg/kg (5 mg/lb) every 24 hours. More severe infections —one intramuscular injection of 10 mg/kg (5 mg/lb) every 12 hours or more often. INTRAVENOUS— Adults: The intravenous dose will be determined by the severity of the infection. For serious infections doses of 600 mg of lincomycin (2 mL of lincomycin injection) to 1 gram are given every 8 to 12 hours. For more severe infections these doses may have to be increased. In life-threatening situations daily intravenous doses of as much as 8 grams have been given. Intravenous doses are given on the basis of 1 gram of lincomycin diluted in not less than 100 mL of appropriate solution (see PHYSICAL COMPATIBILITIES ) and infused over a period of not less than one hour. Dose Vol. Diluent Time 600 mg 100 mL 1 hr 1 gram 100 mL 1 hr 2 grams 200 mL 2 hr 3 grams 300 mL 3 hr 4 grams 400 mL 4 hr These doses may be repeated as often as required to the limit of the maximum recommended daily dose of 8 grams of lincomycin. Pediatric patients over 1 month of age: 10 to 20 mg/kg/day (5 to 10 mg/lb/day) depending on the severity of the infection may be infused in divided doses as described above for adults. NOTE: Severe cardiopulmonary reactions have occurred when lincomycin injection has been given at greater than the recommended concentration and rate (see PRECAUTIONS ). SUBCONJUNCTIVAL INJECTION— 0.25 mL (75 mg) injected subconjunctivally will result in ocular fluid concentrations of antibacterial (lasting for at least 5 hours) sufficient for most susceptible pathogens. Patients with Renal Impairment When therapy with lincomycin injection is required in individuals with severe renal impairment, an appropriate dose is 25 to 30% of that recommended for patients with normally functioning kidneys (see PRECAUTIONS ). Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

WARNINGS See BOXED WARNING . Clostridioides difficile associated diarrhea Clostridioides difficile associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including Lincomycin, 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 antibacterial 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 antibacterial use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibacterial treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated. Hypersensitivity Severe hypersensitivity reactions, including anaphylactic reactions and severe cutaneous adverse reactions (SCAR) such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), acute generalized exanthematous pustulosis (AGEP), and erythema multiforme (EM) have been reported in patients receiving Lincomycin Injection, USP therapy. If an anaphylactic reaction or severe skin reaction occurs, Lincomycin Injection, USP should be discontinued and appropriate therapy should be initiated. (See ADVERSE REACTIONS ) Benzyl Alcohol Toxicity in Pediatric Patients (Gasping Syndrome) Lincomycin injection contains benzyl alcohol as a preservative. The preservative benzyl alcohol has been associated with serious adverse events, including the "gasping syndrome", and death in pediatric patients. Although normal therapeutic doses of this product ordinarily deliver amounts of benzyl alcohol that are substantially lower than those reported in association with the "gasping syndrome", the minimum amount of benzyl alcohol at which toxicity may occur is not known. The risk of benzyl alcohol toxicity depends on the quantity administered and the liver and kidneys' capacity to detoxify the chemical. Premature and low-birth weight infants may be more likely to develop toxicity. Inadequate for Use in Meningitis Although lincomycin appears to diffuse into cerebrospinal fluid, concentrations of lincomycin in the CSF may be inadequate for the treatment of meningitis.

CONTRAINDICATIONS Lincomycin injection is contraindicated in patients previously found to be hypersensitive to lincomycin or clindamycin.

Information for Patients Patients should be counseled that antibacterial drugs including lincomycin injection should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When lincomycin injection is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by lincomycin injection or other antibacterial drugs in the future. Diarrhea is a common problem caused by antibacterial which usually ends when the antibacterial is discontinued. Sometimes after starting treatment with antibacterial, patients can develop watery and bloody stools (with or without stomach cramps and fever) even as late as two or more months after having taken the last dose of the antibacterial. If this occurs, patients should contact their physician as soon as possible. Drug Interactions Lincomycin has been shown to have neuromuscular blocking properties that may enhance the action of other neuromuscular blocking agents. Therefore, it should be used in caution in patients receiving such agents.

ADVERSE REACTIONS The following reactions have been reported with the use of lincomycin and are listed by System Organ Class. Frequencies are defined as: commom (≥1% and<10%) uncommon (≥0.1% and <1%), rare (≥0.01% and <0.1%) and not known (cannot be estimated from the available data). Gastrointestinal disorders Common: persistent diarrhea (4.3%), nausea (1.8%), vomiting (1.6%) Rare: stomatitis (0.04%) Not known: glossitis, abdominal discomfort, and pruritus Skin and subcutaneous tissue disorders Uncommon: rash (0.8%), urticaria (0.1%) Rare: pruritus (0.4%) Infections and infestations Uncommon: vaginal infection (0.12%) Not known: pseudomembranous colitis, Clostridium difficile colitis (see WARNINGS ) Blood and lymphatic system disorders Not known: pancytopenia, agranulocytosis, aplastic anemia, leukopenia, neutropenia, thrombocytopenic purpura Immune system disorders Not known: anaphylactic reaction (see WARNINGS ) angioedema, serum sickness Hepatobiliary disorders Not known: jaundice, liver function test abnormal, transaminases increased Renal and urinary disorders Not known: renal impairment, oliguria, proteinuria, azotemia ¹No direct relationship of LINCOCIN to renal damage has been established. Cardiac disorders Not known: cardio-respiratory arrest (see DOSAGE AND ADMINISTRATION) Vascular disorders Not known: hypotension (see DOSAGE AND ADMINISTRATION ), thrombophlebitis² ²Event has been reported with intravenous injection. Ear and labyrinth disorders Not known: vertigo, tinnitus Not known: injection site abscess sterile³, injection site induration³, injection site pain³, injection site irritation³ ³Reported with intramuscular injection.

CLINICAL PHARMACOLOGY Intramuscular administration of a single dose of 600 mg of lincomycin produces average peak serum concentrations of 11.6 mcg/mL at 60 minutes and maintains therapeutic concentrations for 17 to 20 hours for most susceptible gram-positive organisms. Urinary excretion after this dose ranges from 1.8 to 24.8 percent (mean: 17.3 percent). A two hour intravenous infusion of 600 mg of lincomycin achieves average peak serum concentrations of 15.9 mcg/mL and maintains therapeutic concentrations for 14 hours for most susceptible gram-positive organisms. Urinary excretion ranges from 4.9 to 30.3 percent (mean: 13.8 percent). The biological half-life after intramuscular or intravenous administration is 5.4 ± 1.0 hours. The serum half-life of lincomycin may be prolonged in patients with severe renal impairment compared to patients with normal renal function. In patients with hepatic impairment, serum half-life may be twofold longer than in patients with normal hepatic function. Hemodialysis and peritoneal dialysis are not effective in removing lincomycin from the serum. Tissue distribution studies indicate that bile is an important route of excretion. Significant concentrations have been demonstrated in most body tissues. Although lincomycin appears to diffuse into cerebrospinal fluid (CSF), concentrations of lincomycin in the CSF appear inadequate for the treatment of meningitis. Microbiology: Mechanism of Action Lincomycin inhibits bacterial protein synthesis by binding to the 23S RNA of the 50S subunit of the bacterial ribosome. Lincomycin is predominantly bacteriostatic in vitro . Resistance Cross resistance has been demonstrated between clindamycin and lincomycin. Resistance is most often due to methylation of specific nucleotides in the 23S RNA of the 50S ribosomal subunit, which can determine cross resistance to macrolides and streptogramins B (MLSB phenotype). Macrolide-resistant isolates of these organisms should be tested for inducible resistance to lincomycin/clindamycin using the D-zone test or other appropriate method. Antimicrobial Activity Lincomycin has been shown to be active against most strains of the following bacteria both in vitro and in clinical infections: (see INDICATIONS AND USAGE ). Staphylococcus aureus Streptococcus pneumoniae The following in vitro data are available, but their clinical significance is unknown. Lincomycin has been shown to be active in vitro against the following microorganisms; however, the safety and efficacy of lincomycin in treating clinical infections due to these organisms have not been established in adequate and well controlled trials. Gram-positive bacteria: Corynebacterium diphtheriae Streptococcus pyogenes Viridans group streptococci Anaerobic bacteria: Clostridium tetani Clostridium perfringens Susceptibility Testing For specific information regarding susceptibility test interpretive criteria and associated test methods and quality control standards recognized by FDA for this drug, please see: https://www.fda.gov/STIC.