Clindamycin

 Risk Factor: BM
 Class: ANTI-INFECTIVES / Antibiotics/Anti-infectives

Contents of this page:

Fetal Risk Summary
Breast Feeding Summary
References
Questions and Answers

Fetal Risk Summary

No reports linking the use of clindamycin with congenital defects have been located. Reproduction studies in mice and rats with oral doses up to 600 mg/kg/day (about 1.1 and 2.1 times the maximum recommended human adult dose on a mg/m2 basis [MRHD], respectively) revealed no evidence of teratogenicity (1). SC doses in the two species up to 250 mg/kg/day (0.5 and 0.9 times the MRHD, respectively) also failed to show teratogenicity (1).

The drug crosses the placenta, achieving maximum cord serum levels of approximately 50% of the maternal serum (2, 3). Levels in the fetus were considered therapeutic for susceptible pathogens. A study published in 1988 measured a mean cord:maternal ratio of 0.15 in three women given an unknown amount of clindamycin in labor for the treatment of chorioamnionitis (4). At the time of sampling, mean maternal blood, cord blood, and placental membrane concentrations of the antibiotic were 1.67 g/mL, 0.26 g/mL, and 1.86 g/g, respectively (placenta:maternal ratio 1.11). Fetal tissue levels increase following multiple dosing with the drug, concentrating in the fetal liver (2). Maternal serum levels after dosing at various stages of pregnancy were similar to those of nonpregnant patients (3, 5). Clindamycin has been used for prophylactic therapy prior to cesarean section (6).

In a surveillance study of Michigan Medicaid recipients involving 229,101 completed pregnancies conducted between 1985 and 1992, 647 newborns had been exposed to clindamycin during the 1st trimester (includes both maternal systemic and nonsystemic administration) (F. Rosa, personal communication, FDA, 1993). A total of 31 (4.8%) major birth defects were observed (28 expected). Specific data were available for six defect categories, including (observed/expected) 5/6 cardiovascular defects, 0/1 oral clefts, 1/0.5 spina bifida, 1/2 polydactyly, 0/1 limb reduction defects, and 3/2 hypospadias. These data do not support an association between the drug and congenital defects.

Breast Feeding Summary

Clindamycin is excreted into breast milk. In two patients receiving 600 mg IV every 6 hours, milk levels varied from 2.13.8 g/mL (0.23.5 hours after drug) (7). When the patients were changed to 300 mg orally every 6 hours, levels varied from 0.71.8 g/mL (27 hours after drug). Maternal serum levels were not given.

Two grossly bloody stools were observed in a nursing infant whose mother was receiving clindamycin and gentamicin (8). No relationship to either drug could be established. However, the condition cleared rapidly when breast feeding was stopped. Except for this one case, no other adverse effects in nursing infants have been reported.

Three potential problems that may exist for the nursing infant are modification of bowel flora, direct effects on the infant, and interference with the interpretation of culture results if a fever workup is required. The American Academy of Pediatrics considers clindamycin to be compatible with breast feeding (9).

References

1. Product information. Cleocin. Pharmacia & Upjohn, 2000.
2. Philipson A, Sabath LD, Charles D. Transplacental passage of erythromycin and clindamycin. N Engl J Med 1973;288:121921.
3. Weinstein AJ, Gibbs RS, Gallagher M. Placental transfer of clindamycin and gentamicin in term pregnancy. Am J Obstet Gynecol 1976;124:68891.
4. Gilstrap LC III, Bawdon RE, Burris J. Antibiotic concentration in maternal blood, cord blood, and placental membranes in chorioamnionitis. Obstet Gynecol 1988;72:1245.
5. Philipson A, Sabath LD, Charles D. Erythromycin and clindamycin absorption and elimination in pregnant women. Clin Pharmacol Ther 1976;19:6877.
6. Rehu M, Jahkola M. Prophylactic antibiotics in caesarean section: effect of a short preoperative course of benzyl penicillin or clindamycin plus gentamicin on postoperative infectious morbidity. Ann Clin Res 1980;12:458.
7. Smith JA, Morgan JR, Rachlis AR, Papsin FR. Clindamycin in human breast milk. Can Med Assoc J 1975;112:806.
8. Mann CF. Clindamycin and breast-feeding. Pediatrics 1980;66:10301.
9. Committee on Drugs, American Academy of Pediatrics. The transfer of drugs and other chemicals into human milk. Pediatrics 1994;93:13750.