Clindamycin Hydrochloride, Clindamycin Palmitate Hydrochloride, Clindamycin Phosphate: Uses
Clindamycin generally is used for the treatment of serious infections caused by susceptible gram-positive bacteria and for the treatment of serious infections caused by susceptible anaerobic bacteria. Because the risk of severe, potentially fatal Clostridium difficile-associated diarrhea and colitis may be higher with clindamycin than with certain other anti-infectives, use of the drug should be limited to serious infections for which less toxic and/or more effective anti-infectives are not readily available.
However, it should be noted that C. difficile diarrhea and colitis has been associated with the use of nearly all anti-infectives, being reported most frequently with clindamycin, cephalosporins, and ampicillin; second and third generation cephalosporins play an increasingly important role.Empiric therapy with clindamycin in infections that are highly likely to be nonbacterial in origin (e.g., many upper respiratory tract infections) should be avoided. Prior to initiation of clindamycin therapy, the causative organism should be cultured and susceptibility tests conducted. Clindamycin therapy does not obviate incision, drainage, or certain other surgical procedures when indicated. Because clindamycin does not distribute adequately into the CNS, the drug should not be used for the treatment of meningitis.
Gram-positive Aerobic Bacterial Infections
Clindamycin is used parenterally in the treatment of bone and joint infections (including acute hematogenous osteomyelitis) caused by Staphylococcus aureus and as an adjunct to surgery in the treatment of chronic bone and joint infections caused by susceptible organisms.
Clindamycin also is used orally or parenterally in the treatment of serious respiratory tract infections, skin and skin structure infections, or septicemia caused by susceptible strains of S. aureus, Streptococcus pneumoniae, or other streptococci (except Enterococcus faecalis [formerly S. faecalis]).
However, clindamycin is not considered the drug of choice in infections caused by gram-positive aerobic cocci and its use in these infections should be reserved for penicillin-allergic patients or other patients for whom less toxic alternatives are contraindicated. Clindamycin should not be used for the treatment of minor bacterial skin or dental infections or for nonbacterial upper respiratory tract infections.
Anaerobic Bacterial Infections
Clindamycin is used orally or parenterally in the treatment of serious lower respiratory tract infections (including empyema, pneumonia, and lung abscess), serious skin and skin structure infections, septicemia, intra-abdominal infections (including peritonitis and intra-abdominal abscess), and gynecologic infections (including endometritis, nongonococcal tubo-ovarian abscess, pelvic cellulitis, and postsurgical vaginal cuff infections) caused by susceptible anaerobic bacteria.
Parenteral clindamycin also is used in the treatment of bone and joint infections (including acute hematogenous osteomyelitis) and as adjunctive therapy in the surgical treatment of chronic bone and joint infections caused by susceptible organisms.
Most clinicians consider clindamycin to be a drug of choice for the treatment of infections caused by Bacteroides, including those caused by oropharyngeal strains of B. fragilis or B. melaninogenicus that often are penicillin resistant or do not respond to penicillin G. In the treatment of mixed aerobic-anaerobic bacterial infections, clindamycin has been used in conjunction with an IM or IV aminoglycoside.
Pelvic Inflammatory Disease
The US Centers for Disease Control and Prevention (CDC) and many clinicians currently suggest IV clindamycin in combination with an IV or IM aminoglycoside (e.g., gentamicin) as one possible parenteral regimen for the treatment of acute pelvic inflammatory disease (PID) in adults and adolescents. PID is a polymicrobial infection most frequently caused by N. gonorrhoeae and/or Chlamydia trachomatis; however, organisms that can be part of the normal vaginal flora (e.g., anaerobic bacteria, Garnerella vaginalis, H. influenzae, enteric gram-negative bacilli, S. agalactiae) or mycoplasma (e.g., Mycoplasma hominis, Ureaplasma urealyticum) also may be involved. PID is treated with an empiric regimen that provides broad-spectrum coverage.
The regimen should be effective against N. gonorrhoeae and C. trachomatis and also probably should be effective against anaerobes, gram-negative facultative bacteria and streptococci. In addition, women with PID often have bacterial vaginosis concurrently, a polymicrobial infection that includes anaerobes. The optimum regimen for the treatment of PID has not been identified. A variety of parenteral and oral regimens have been recommended by the CDC and other clinicians. The clindamycin-aminoglycoside regimen provides good coverage for anaerobes.
The parenteral regimen may be discontinued 24 hours after the patient improves clinically and then an oral regimen of either doxycycline (100 mg twice daily) or clindamycin (450 mg 4 times daily) is used to complete 14 days of therapy. If tubo-ovarian abscess is present, many clinicians prefer clindamycin for follow-up oral therapy since it provides more effective coverage against anaerobes than doxycycline.
The clindamycin-aminoglycoside regimen may not provide optimal coverage for N. gonorrhoeae and C. trachomatis, and a regimen consisting of IV cefoxitin or IV cefotetan and oral doxycycline may be preferred for the treatment of PID when these organisms are suspected as the primary pathogens. However, if one of these regimen is used when tubo-ovarian abscess is present, many clinicians recommend use of clindamycin or metronidazole for follow-up oral therapy (instead of oral doxycycline) to provide more effective anaerobic coverage.
Bacterial Vaginosis
Oral clindamycin is used for the treatment of bacterial vaginosis (formerly called Haemophilus vaginitis, Gardnerella vaginitis, nonspecific vaginitis, Corynebacterium vaginitis, or anaerobic vaginosis). The drug also is used intravaginally as a vaginal cream for the treatment of bacterial vaginosis.
Goals of treatment and recommended therapy differ for nonpregnant versus pregnant women. However, relief of signs and symptoms of infection is a principal goal of therapy, and all women with symptomatic bacterial vaginosis should be treated regardless of pregnancy status.
Nonpregnant Women
The CDC recommended regimens for treatment of bacterial vaginosis in nonpregnant women are a 7-day regimen of oral metronidazole (500 mg twice daily); a 5-day regimen of intravaginal metronidazole gel; or a 7-day regimen of intravaginal clindamycin cream.
Alternative regimens recommended by the CDC for these women are a single 2-g oral dose of metronidazole; a 7-day regimen of oral clindamycin (300 mg daily); or a 3-day regimen of intravaginal clindamycin suppositories.Intravaginal metronidazole results in clinical cure rates comparable to those of oral metronidazole therapy, and some clinicians prefer initial topical therapy because of the reduced risk of adverse systemic effects.
Regardless of the therapy chosen, relapse or recurrence of bacterial vaginosis is common, and some clinicians suggest that an alternative regimen (e.g., oral therapy when topical therapy was used initially) can be employed in such infections. A 7-day course of oral clindamycin (300 mg twice daily) may be used as an alternative regimen for the treatment of bacterial vaginosis in nonpregnant women (e.g., for treatment of relapse or recurrence following initial topical therapy, for initial therapy in patients in whom therapy with systemic metronidazole is contraindicated or not tolerated).
However, experience with oral metronidazole is far more extensive and studies of comparative efficacy with oral clindamycin are limited. The CDC suggests that intravaginal or oral clindamycin is the preferred regimen for the treatment of bacterial vaginosis in women hypersensitive to metronidazole. Long-term maintenance therapy does not appear to be beneficial in women with recurrent or relapsing disease and is not recommended.
Pregnant Women
An increased risk of obstetric complications, including intraamniotic infection, chorioamnionitis, premature rupture of membranes, preterm delivery, and low-birthweight infants, is associated with the presence of bacterial vaginosis in pregnant women, and the organisms found in increased concentrations in the genital flora of women with bacterial vaginosis are frequently found in patients with postpartum or postcesarean endometritis.
Evidence from randomized, controlled trials indicates that systemic treatment of bacterial vaginosis reduces the rate of preterm birth in pregnant women at high risk for complications of pregnancy. Because of the increased risk of adverse pregnancy outcomes associated with the presence of bacterial vaginosis, the CDC recommends that all symptomatic pregnant women be tested and treated for bacterial vaginosis. In addition, because there is evidence from randomized studies that treatment of bacterial vaginosis in asymptomatic pregnant women at high risk for complications of pregnancy (e.g., those who previously delivered of a premature infant) has reduced preterm delivery, some experts recommend that all women at high risk be screened and treated for bacterial vaginosis. In asymptomatic pregnant women, the CDC currently recommends screening and treatment only in those who are at high risk for complications of pregnancy (i.e., in women with previous preterm birth) and recommends that such screening and treatment be performed at the first prenatal visit. (See Uses: Bacterial Vaginosis in Metronidazole 8:30.04.)
The preferred regimens for the treatment of symptomatic bacterial vaginosis in pregnant women and for the treatment of asymptomatic pregnant women at high risk for complications of pregnancy are a 7-day course of oral metronidazole (250 mg 3 times daily) or a 7-day course of oral clindamycin (300 mg daily).
Although placebo-controlled studies showed that intravaginal clindamycin is an effective treatment for bacterial vaginosis in pregnant women (approximately 10% of whom had a history of preterm delivery or low-birthweight infant placing them at high risk for complications of pregnancy), such therapy did not reduce the incidence of adverse pregnancy outcomes; thus, use of intravaginal clindamycin for prevention of adverse pregnancy outcomes associated with bacterial vaginosis in women at high risk for preterm delivery is not recommended. While the CDC and some experts state that use of clindamycin vaginal cream is not recommended during pregnancy, other experts suggest that use of intravaginal clindamycin may be acceptable for symptomatic relief of bacterial vaginosis in women at low risk for adverse pregnancy outcomes.
Intravaginal metronidazole may be an acceptable alternative regimen for the treatment of symptomatic bacterial vaginosis in pregnant women at low risk for adverse pregnancy outcomes.Although some experts agree that topical therapy may be used solely for symptomatic relief (and not for prevention of adverse pregnancy outcomes) in women at low risk for preterm delivery, others prefer use of systemic therapy for all pregnant women, regardless of degree of risk for complications of pregnancy, because systemic treatment may be required to eradicate upper genital tract infection that may be associated with bacterial vaginosis.
No adequate and controlled studies have been performed to date to establish the safety and efficacy of intravaginal metronidazole for the treatment of bacterial vaginosis in pregnant women, and further study is needed to establish the optimal treatment of bacterial vaginosis in pregnant women.
Because recurrence of bacterial vaginosis is not unusual, and the treatment of this condition may prevent adverse pregnancy outcomes, particularly in women at high risk for complications of pregnancy, follow-up at 1 month to assess for cure and evaluate the need for additional treatment should be considered. If bacterial vaginosis persists, additional therapy (e.g., second course of oral therapy in a pregnant woman at high risk for preterm delivery) or an alternative regimen (e.g., oral therapy when topical therapy was used initially in a pregnant woman at low risk for complications of pregnancy) may be used to treat relapsed or recurrent disease.
HIV-infected Women
Recommendations for treatment and preferred regimens for bacterial vaginosis in patients with concurrent human immunodeficiency virus (HIV) infection are the same as those for patients without HIV infection.
Sexual Contacts
Results of several randomized, double-blind, placebo-controlled trials indicate that concurrent treatment of male sexual contacts of a woman with symptomatic bacterial vaginosis generally does not appear to affect the clinical cure rate, including the risk of relapse or recurrence of the syndrome, in the woman. Therefore, routine treatment of male sexual contacts currently is not recommended. However, despite the lack of controlled studies showing any benefit, some clinicians believe that treatment of male sexual contacts (with similar oral dosages) of women who have relapsing or recurrent bacterial vaginosis may be reasonable. Further study is needed to elucidate the possible role, if any, of sexual transmission in bacterial vaginosis.
Prevention of Perinatal Group B Streptococcal Diseas
IV clindamycin is used as an alternative to parenteral penicillin G or ampicillin for prevention of perinatal group B streptococcal (GBS) disease in certain women who are hypersensitive to penicillins.
Pregnant women who are colonized with GBS in the genital or rectal areas can transmit GBS infection to their infants during labor and delivery resulting in invasive neonatal infection that can be associated with substantial morbidity and mortality. Intrapartum anti-infective prophylaxis for prevention of early-onset neonatal GBS disease is administered selectively to women at high risk for transmitting GBS infection to their neonates.
When intrapartum prophylaxis is indicated in the mother, penicillin G is the regimen of choice and ampicillin is the preferred alternative. When intrapartum prophylaxis to prevent GBS in the neonate is indicated in women who are hypersensitive to penicillins, the CDC recommends a regimen of IV clindamycin or IV erythromycin for those allergic to penicillins who are at high risk for anaphylaxis (e.g., those with a history of immediate penicillin hypersensitivity, such as anaphylaxis, angioedema, or urticaria; those with a history of asthma or other conditions that would make anaphylaxis more dangerous or difficult to treat, including individuals receiving adrenergic blocking agents).
For those allergic to penicillins who are not at high risk for anaphylaxis, the CDC states that a regimen of IV cefazolin should be used since this cephalosporin has a narrow spectrum of activity and is associated with high intraamniotic concentrations.
The fact that S. agalactiae (group B streptococci) with in vitro resistance to clindamycin and erythromycin have been reported with increasing frequency should be considered when choosing an alternative to penicillins. When use of erythromycin or clindamycin is being considered in a women hypersensitive to penicillin, in vitro susceptibility testing of clinical isolates obtained during GBS prenatal screening should be performed whenever possible to determine if the isolates are susceptible to these drugs. Strains of GBS resistant to erythromycin often are resistant to clindamycin, although this may not be evident in results of in vitro testing.
If in vitro susceptibility testing is not possible, results are unknown, or isolates are found to be resistant to erythromycin or clindamycin, a regimen of vancomycin should be used for intrapartum prophylaxis in women with penicillin allergy who are at high risk for anaphylaxis.
Prevention of Bacterial Endocarditis
Clindamycin is used as an alternative agent for prevention of a-hemolytic (viridans group) streptococcal bacterial endocarditis in penicillin-allergic adults and children with congenital heart disease, rheumatic or other acquired valvular heart dysfunction (even after valvular surgery), prosthetic heart valves (including bioprosthetic and allograft valves), surgically constructed systemic pulmonary shunts or conduits, hypertrophic cardiomyopathy, mitral valve prolapse with valvular regurgitation and/or thickened leaflets, or previous bacterial endocarditis (even in the absence of heart disease) who undergo certain dental and upper respiratory tract procedures likely to cause transient bacteremia and increase the risk of endocarditis.
These procedures include dental and oral procedures that are likely to result in gingival or mucosal bleeding (i.e., dental extractions; periodontal procedures such as scaling, root planing, probing, and maintenance; dental implant placement or reimplantation of avulsed teeth; root-filling procedures; subgingival placement of antibiotic fibers or strips; initial placement of orthodontic bands; intraligamentary local anesthetic injections; routine professional cleaning) and minor upper respiratory tract surgery or instrumentation (e.g., tonsillectomy, adenoidectomy, bronchoscopy with a rigid bronchoscope).
The American Heart Association (AHA) recognizes that its current recommendations for prophylaxis against bacterial endocarditis are empiric, since no controlled efficacy studies have been published, and that prophylaxis of endocarditis is not always effective.
However, the AHA, the American Dental Association (ADA), and most clinicians generally recommend routine use of prophylactic anti-infectives in patients with the cardiac conditions described above since these are associated with a high or moderate risk for bacterial endocarditis. The AHA, ADA, and others state that prophylaxis against bacterial endocarditis is not recommended for adults or children with cardiac conditions considered to be associated with a negligible risk for endocarditis since these individuals are at no greater risk than the general population.
Therefore, prophylaxis against bacterial endocarditis is not considered necessary for individuals with a history of isolated secundum atrial septal defect; surgical repair of atrial septal defect, ventricular septal defect, or patent ductus arteriosus (without residua beyond 6 months); previous coronary artery bypass graft surgery; mitral valve prolapse without valvar regurgitation; physiologic, functional, or innocent heart murmurs; previous Kawasaki disease without valvar dysfunction; previous rheumatic fever without valvar dysfunction; or cardiac pacemaker (intravascular and epicardial) and implanted defibrillators. When selecting anti-infectives for prophylaxis of recurrent rheumatic fever or prophylaxis of bacterial endocarditis, the current recommendations published by the AHA should be consulted.
Toxoplasmosis
Treatment Combination therapy with clindamycin and pyrimethamine has been used with some success for the treatment of cerebral and/or ocular toxoplasmosis in immunocompromised patients (e.g., those with AIDS) unable to tolerate (because of the sulfonamide component) combination therapy with pyrimethamine and sulfadiazine and also has been used in those whose disease relapsed with pyrimethamine and sulfadiazine therapy.Leucovorin usually is added to pyrimethamine and clindamycin therapy to prevent pyrimethamine-induced adverse hematologic effects.
Prevention
Because recurrence of toxoplasmosis has been reported commonly following initial recovery and/or discontinuance of anti-infective therapy in immunocompromised patients, prolonged anti-infective therapy usually is necessary for the treatment of acute toxoplasmosis in such patients; long-term suppressive therapy may be necessary.
The Prevention of Opportunistic Infections Working Group of the US Public Health Service and the Infectious Diseases Society of America (USPHS/IDSA) have established guidelines for the prevention of opportunistic infections, including toxoplasmosis, in HIV-infected individuals that include recommendations concerning prevention of exposure to opportunistic pathogens, prevention of first disease episodes, and prevention of disease recurrence.
The USPHS/IDSA currently recommends combination therapy with pyrimethamine and sulfadiazine as the regimen of choice for long-term suppressive therapy (secondary prophylaxis or chronic maintenance therapy) to prevent relapse of toxoplasmosis in HIV-infected adults, adolescents, infants, and children.
When this regimen cannot be used (e.g., in patients who cannot tolerate sulfonamides), combination therapy with pyrimethamine and clindamycin is recommended as an alternative regimen for long-term suppressive therapy. However, in a prospective, randomized study in HIV-infected patients with initial episodes of toxoplasmic encephalitis, the relapse rate was higher in patients who received initial and maintenance therapy with clindamycin in conjunction with pyrimethamine than in those who received a regimen of sulfadiazine in conjunction with pyrimethamine. In addition, only the pyrimethamine/sulfadiazine regimen appears to provide protection against both toxoplasmosis and Pneumocystis jiroveci (formerly known as Pneumocystis carinii) pneumonia.
Long-term suppressive therapy to prevent relapse or recurrence of toxoplasmosis in HIV-infected individuals generally is continued for life, unless immune recovery has occurred as the result of potent antiretroviral therapy.
Limited data indicate that HIV-infected adults and adolescents who have successfully completed initial therapy for toxoplasmic encephalitis remain asymptomatic with respect to toxoplasmic encephalitis and have CD4+ T-cell counts greater than 200/mm3 as the result of potent antiretroviral therapy that have been sustained for 6 months or longer are at low risk for recurrence of toxoplasmic encephalitis.
Based on these data and more extensive cumulative data on safety of discontinuing secondary prophylaxis for other opportunistic infections, the USPHS/IDSA states that it is reasonable to consider discontinuing secondary toxoplasmosis prophylaxis in adults and adolescents meeting these criteria. Some experts would obtain a magnetic resonance image of the brain as part of their evaluation to determine whether or not discontinuance of prophylaxis is appropriate.
The USPHS/IDSA states that secondary prophylaxis against toxoplasmosis should be restarted in adults and adolescents if CD4+ T-cell counts decrease to less than 200/mm3. The safety of discontinuing secondary toxoplasmosis prophylaxis in HIV-infected children receiving potent antiretroviral therapy has not been extensively studied.
Pneumocystis jiroveci (Pneumocystis carinii) Pneumonia
Treatment
Clindamycin is used in conjunction with primaquine for the treatment of mild to moderately severe Pneumocystis jiroveci (formerly Pneumocystis carinii) pneumonia (PCP) in HIV-infected adults. Clindamycin is designated an orphan drug by the US Food and Drug Administration (FDA) for use in this condition. Results of clinical studies indicate that clindamycin administered IV (1.-3. g given in 3 or 4 divided doses daily) or orally (1.2-3.6 g in 3 or 4 divided doses daily [in some cases oral clindamycin was administered after initial IV administration]) in conjunction with oral primaquine (15 or 30 mg daily) for a total 21 days of therapy is effective for the treatment of PCP in HIV-infected individuals. Most patients exhibit clinical improvement within 2-7 days, and the combination generally appears to be well tolerated.
Combined therapy with clindamycin and primaquine appears to be an effective alternative to co-trimoxazole, at least in patients with mild to moderately severe PCP, and the combination can be considered for patients who have had an inadequate response to co-trimoxazole or when co-trimoxazole is contraindicated or not tolerated.
Prevention
While a regimen of clindamycin and primaquine has been used as an alternative to usual regimens for prevention of recurrence (secondary prophylaxis or chronic maintenance therapy) of PCP in a limited number of AIDS patients, the USPHS/IDSA generally does not recommend this combination for prophylaxis of PCP in HIV-infected individuals because current data are insufficient to determine efficacy of the regimen. Instead, the USPHS/IDSA states that a regimen of clindamycin and primaquine can be considered for primary or secondary prophylaxis of PCP in unusual situations when the usually recommended agents (co-trimoxazole, dapsone, dapsone with pyrimethamine and leucovorin, aerosolized pentamidine, atovaquone) cannot be administered. Clindamycin is designated an orphan drug by the FDA for use in this condition.
Perioperative Prophylaxis
IV clindamycin is used perioperatively to reduce the incidence of infections in patients undergoing clean, contaminated head and neck surgery.
While perioperative prophylaxis does not appear to reduce the rate of infection in patients undergoing clean procedures involving the head and neck (e.g., parotidectomy, thyroidectomy, submandibular-gland excision), there is evidence that antimicrobial prophylaxis decreases the incidence of postoperative infection following head and neck surgery involving an incision through oral or pharyngeal mucosa.
The preferred regimens for perioperative prophylaxis in patients undergoing clean, contaminated head or neck surgery are IV clindamycin given with IV gentamicin or, alternatively, IV cefazolin.
Clindamycin also has been used for perioperative prophylaxis in patients undergoing certain intra-abdominal procedures such as appendectomy. While some clinicians recommend a regimen of ampicillin, gentamicin, and clindamycin for perioperative prophylaxis in children undergoing nonperforated appendectomy, either cefoxitin or cefotetan generally is used when a parenteral regimen is indicated for perioperative prophylaxis in patients undergoing colorectal surgery or appendectomy and cefazolin generally is the preferred agent for perioperative prophylaxis in patients undergoing gastroduodenal or biliary tract surgery.
Some clinicians suggest that a regimen of IV clindamycin and IV gentamicin may be used as an alternative to IV cefoxitin or IV cefotetan (with or without IV gentamicin) for prophylaxis following contaminated or dirty surgery such as that involving a perforated abdominal viscus. When indicated in this situation, antimicrobial therapy is continued postoperatively for about 5 days and is considered treatment rather than prophylaxis. Ruptured viscus in postoperative setting (dehiscence) requires anti-infectives that include coverage for nosocomial pathogens.
Malaria
Oral clindamycin is used in conjunction with oral quinine sulfate for the treatment of uncomplicated chloroquine-resistant Plasmodium falciparum malaria in adults and children. Clindamycin is not effective when used alone for the treatment of malaria.
Many clinicians recommend that chloroquine-resistant P. falciparum malaria be treated with a regimen of quinine sulfate used in conjunction with doxycycline, tetracycline, pyrimethamine and sulfadoxine, or clindamycin. The quinine sulfate and clindamycin regimen may be preferred for the treatment of young children or pregnant women who should not receive tetracyclines.
Clindamycin also has been used in conjunction with quinine for the treatment of severe P. falciparum malaria. In a limited study in children with severe P. falciparum malaria, a 4-day regimen of IV clindamycin and IV quinine (not commercially available in the US) was as effective as a 7-day regimen of IV quinine; however, clearance of parasites and fever occurred sooner in those receiving the 2-drug regimen.
Acne
Oral clindamycin has been used for the treatment of inflammatory acne vulgaris. For information on use of topical clindamycin in the treatment of inflammatory acne vulgaris.
Anthrax
Although limited clinical data are available regarding use of clindamycin in the treatment of anthrax, clindamycin was included in a multiple-drug regimen that was effective for the treatment of several patients in the US who developed anthrax during September and October 2001 following exposure to an intentional release of anthrax spores (biologic warfare, bioterrorism).
At least 2 patients received a parenteral regimen of ciprofloxacin (400 mg every 8 hours), rifampin (300 mg every 12 hours), and clindamycin (900 mg every 8 hours) for treatment.
Because of the rapid course of symptomatic inhalational anthrax and high mortality rate, prompt recognition of symptoms and early initiation of anti-infective therapy is essential. The CDC and other experts (e.g., the US Working Group on Civilian Biodefense) recommend that treatment of inhalational anthrax that occurs as the result of exposure to anthrax spores in the context of biologic warfare or bioterrorism should be initiated with a multiple-drug parenteral regimen that includes ciprofloxacin or doxycycline and 1 or 2 additional anti-infective agents predicted to be effective.
Multiple-drug parenteral regimens also are recommended for the treatment of cutaneous anthrax if there are signs of systemic involvement, extensive edema, or lesions on the head and neck. Based on in vitro data, drugs that have been suggested as possibilities to augment ciprofloxacin or doxycycline in such multiple-drug regimens include chloramphenicol, clindamycin, rifampin, vancomycin, clarithromycin, imipenem, penicillin, or ampicillin.
Strains of Bacillus anthracis that were associated with cases of inhalational or cutaneous anthrax that occurred in the US (Florida, New York, District of Columbia) during September and October 2001 following bioterrorism-related anthrax exposures were susceptible to clindamycin in vitro.
Babesiosis
Combination therapy with IV clindamycin and oral quinine is used in the treatment of babesiosis caused by Babesia microti. Some clinicians recommend that either a regimen of clindamycin and quinine or a regimen of atovaquone and azithromycin be used when treatment of babesiosis is considered necessary.
The atovaquone and azithromycin regimen appears to be as effective as the clindamycin and quinine regimen and may be better tolerated. Exchange transfusions have been used successfully in asplenic patients with life-threatening babesiosis and should be considered in severely ill patients with high levels of parasitemia (more than 10%).
Pharyngitis and Tonsillitis
Oral clindamycin is used as an alternative agent for the treatment of pharyngitis and tonsillitis caused by S. pyogenes (group A b-hemolytic streptococci). Although clindamycin usually is effective in eradicating S. pyogenes from the nasopharynx, it is not recommended as a drug of choice for treatment of streptococcal pharyngitis and tonsillitis.
Clindamycin is reserved for use as an alternative in patients who cannot receive b-lactam anti-infectives and have infections caused by S. pyogenes resistant to macrolides. In addition, clindamycin is recommended as one of several possible alternatives for the treatment of symptomatic patients who have multiple, recurrent episodes of pharyngitis known to be caused by S. pyogenes.
Because penicillin has a narrow spectrum of activity, is inexpensive, and generally is effective, the CDC, AAP, American Academy of Family Physicians (AAFP), Infectious Diseases Society of American (IDSA),AHA, American College of Physicians-American Society of Internal Medicine (ACP-ASIM), and others consider natural penicillins (i.e., 10 days of oral penicillin V or a single IM dose of penicillin G benzathine) the treatment of choice for streptococcal pharyngitis and tonsillitis and prevention of initial attacks (primary prevention) of rheumatic fever, although oral amoxicillin often is used instead of penicillin V in small children because of a more acceptable taste.
Other anti-infectives (e.g., oral cephalosporins, oral macrolides) generally are considered alternatives. If there is recurrence of signs and symptoms of pharyngitis shortly after the initial recommended anti-infective regimen is completed (i.e., within a few weeks) and presence of S. pyogenes is detected, retreatment with the original regimen or another regimen of choice is indicated. If compliance with a 10-day oral regimen is a concern, IM penicillin G benzathine should be used for retreatment.
Some clinicians suggest use of an alternative agent (e.g., amoxicillin and clavulanate, clindamycin, macrolide) for retreatment.
However, if there are multiple, recurrent episodes of symptomatic pharyngitis within a period of months to years, it may be difficult to determine whether these are true episodes of S. pyogenes infection or whether the patient is a long-term streptococcal pharyngeal carrier who is experiencing repeated episodes of nonstreptococcal pharyngitis (e.g., viral pharyngitis) in whom treatment is not usually indicated.
Continuous anti-infective prophylaxis (secondary prophylaxis) to prevent the recurrence of streptococcal pharyngitis is not recommended in these circumstances, unless the patient has a history of rheumatic fever. Instead, use of an alternative regimen is recommended by some clinicians. Although there are no controlled clinical studies evaluating efficacy, the IDSA suggests that symptomatic individuals with multiple, recurrent episodes of documented S. pyogenes pharyngitis receive a regimen of oral clindamycin, oral amoxicillin clavulanate, or IM penicillin G benzathine (with or without oral rifampin).
Respiratory Tract Infections
Clindamycin is used for the treatment of serious respiratory tract infections (including pneumonia, empyema, lung abscess) caused by susceptible anaerobes, S. pneumoniae, other streptococci, or S. aureus.
If presence of anaerobes are documented or if lung abscess is present in a patient with pneumonia, the American Thoracic Society (ATS) recommends that clindamycin or metronidazole be included in the treatment regimen.
The IDSA states that clindamycin, a b-lactam/b-lactamase inhibitor, imipenem, or meropenem is preferred for the treatment of pulmonary infections if anaerobic bacteria have been identified or are suspected. Some experts consider clindamycin a preferred drug for anaerobic pulmonary infections, including aspiration pneumonia and putrid lung abscess.