CLINDAMYCIN HYDROCHLORIDE

INDICATIONS AND USAGE Clindamycin hydrochloride capsules are indicated in the treatment of serious infections caused by susceptible anaerobic bacteria. Clindamycin hydrochloride capsules are also 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 colitis, as described in the BOXED WARNING , before selecting clindamycin, the physician should consider the nature of the infection and the suitability of less toxic alternatives (e.g., erythromycin). Anaerobes: Serious respiratory tract infections such as empyema, anaerobic pneumonitis, and lung abscess; serious skin and soft tissue infections; septicemia; intra-abdominal infections such as peritonitis and intra-abdominal abscess (typically resulting from anaerobic organisms resident in the normal gastroin­testinal tract); infections of the female pelvis and geni­tal tract such as endometritis, nongonococcal tubo-ovarian abscess, pelvic cellulitis, and postsurgical vaginal cuff infection. Streptococci: Serious respiratory tract infections; seri­ous skin and soft tissue infections. Staphylococci: Serious respiratory tract infections; serious skin and soft tissue infections. Pneumococci: Serious respiratory tract infections. Bacteriologic studies should be performed to deter­mine the causative organisms and their susceptibility to clindamycin. To reduce the development of drug-resistant bacteria and maintain the effectiveness of clindamycin hydrochloride and other antibacterial drugs, clindamycin hydrochloride 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, this antibacterial drug should be discontinued (See BOXED WARNING ). Administer clindamycin hydrochloride capsules with a full glass of water (6 to 8 ounces, approximately 200 to 250 mL) and at least 30 minutes before lying down to reduce the potential for esophageal irritation (See ADVERSE REACTIONS ). Adults: Serious infections - 150 to 300 mg every 6 hours. More severe infections - 300 to 450 mg every 6 hours. Pediatric Patients (who are able to swallow capsules): Serious infections - 8 to 16 mg/kg/day (4 to 8 mg/lb/day) divided into three or four equal doses. More severe infections - 16 to 20 mg/kg/day (8 to 10 mg/lb/day) divided into three or four equal doses. Clindamycin should be dosed based on total body weight regardless of obesity. Clindamycin hydrochloride capsules are not suitable for pediatric patients who are unable to swallow them whole. The capsules do not provide exact mg/kg doses therefore it may be necessary to use the clindamycin palmitate oral solution in some cases. Serious infections due to anaerobic bacteria are usu­ally treated with clindamycin injection. However, in clinically appropriate circum­stances, the physician may elect to initiate treatment or continue treatment with clindamycin hydrochloride capsules. In cases of β-hemolytic streptococcal infections, treat­ment should continue for at least 10 days.

CONTRAINDICATIONS Clindamycin hydrochloride capsules are contraindicated in individuals with a history of hypersensitivity to preparations containing clindamycin or lincomycin.

WARNINGS See BOXED WARNING Clostridioides difficile- Associated Diarrhea Clostridioides difficile- associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including clindamycin hydrochloride, 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. Anaphylactic and Severe Hypersensitivity Reactions Anaphylactic shock and anaphylactic reactions have been reported (See ADVERSE REACTIONS ). Severe hypersensitivity reactions, including severe skin reactions such as toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and Stevens-Johnson syndrome (SJS), some with fatal outcome, have been reported (See ADVERSE REACTIONS ). In case of such an anaphylactic or severe hypersensitivity reaction, discontinue treatment permanently and institute appropriate therapy. A careful inquiry should be made concerning previous sensitivities to drugs and other allergens. Nephrotoxicity Clindamycin is potentially nephrotoxic and cases with acute kidney injury have been reported. Consider monitoring of renal function particularly in patients with pre-existing renal dysfunction or those taking concomitant nephrotoxic drugs. In case of acute kidney injury, discontinue clindamycin hydrochloride when no other etiology is identified. Usage in Meningitis - Since clindamycin does not diffuse adequately into the cerebrospinal fluid, the drug should not be used in the treatment of meningitis.

Drug Interactions Clindamycin has been shown to have neuromuscular blocking properties that may enhance the action of other neuromuscular blocking agents. Therefore, it should be used with caution in patients receiving such agents. Clindamycin is metabolized predominantly by CYP3A4, and to a lesser extent by CYP3A5, to the major metabolite clindamycin sulfoxide and minor metabolite N-desmethylclindamycin. Therefore, inhibitors of CYP3A4 and CYP3A5 may increase plasma concentrations of clindamycin and inducers of these isoenzymes may reduce plasma concentrations of clindamycin. In the presence of strong CYP3A4 inhibitors, monitor for adverse reactions. In the presence of strong CYP3A4 inducers such as rifampicin, monitor for loss of effectiveness. In vitro studies indicate that clindamycin does not inhibit CYP1A2, CYP2C9, CYP2C19, CYP2E1 or CYP2D6 and only moderately inhibits CYP3A4.

ADVERSE REACTIONS The following reactions have been reported with the use of clindamycin. Infections and Infestations: Clostridioides difficile colitis Gastrointestinal: Abdominal pain, pseudomembranous colitis, nausea, vomiting, and diarrhea (See BOXED WARNING ). The onset of pseudomembranous coli­tis symptoms may occur during or after antibacterial treatment (See WARNINGS ). Esophagitis and esophageal ulcer have been reported, particularly when taken in a lying position or with a small amount of water. An unpleasant or metallic taste has been reported after oral administration. Hypersensitivity Reactions: Generalized mild to moder­ate morbilliform-like (maculopapular) skin rashes are the most frequently reported adverse reactions. Vesiculobullous rashes, as well as urticaria, have been observed during drug therapy. Severe skin reactions such as Toxic Epidermal Necrolysis, some with fatal outcome, have been reported (See WARNINGS ). Cases of Acute Generalized Exanthematous Pustulosis (AGEP), erythema multiforme, some resembling Stevens-Johnson syndrome, anaphylactic shock, anaphylactic reaction and hypersensitivity have also been reported. Skin and Mucous Membranes: Pruritus, vaginitis, angioedema and rare instances of exfoliative dermatitis have been reported (See Hypersensitivity Reactions ). Liver: Jaundice and abnormalities in liver function tests have been observed during clindamycin therapy. Renal: Acute kidney injury (See WARNINGS ). Hematopoietic: Transient neutropenia (leukopenia) and eosinophilia have been reported. Reports of agranulocytosis and thrombocytopenia have been made. No direct etiologic relationship to concurrent clindamycin therapy could be made in any of the foregoing. Immune System: Drug reaction with eosinophilia and systemic symptoms (DRESS) cases have been reported. Musculoskeletal: Cases of polyarthritis have been reported.

Pregnancy: Teratogenic effects In clinical trials with pregnant women, the systemic administration of clindamycin during the second and third trimesters, has not been associated with an increased frequency of congenital abnormalities. Clindamycin should be used during the first trimester of pregnancy only if clearly needed. There are no adequate and well-controlled studies in pregnant women during the first trimester of pregnancy. Because animal reproduc­tion studies are not always predictive of the human response, this drug should be used during pregnancy only if clearly needed. Reproduction studies performed in rats and mice using oral doses of clindamycin up to 600 mg/kg/day (3.2 and 1.6 times the highest recommended adult human dose based on mg/m 2 , respectively) or subcuta­neous doses of clindamycin up to 250 mg/kg/day (1.3 and 0.7 times the highest recommended adult human dose based on mg/m 2 , respectively) revealed no evi­dence of teratogenicity.