(clindamycin)
Mechanism of Action
Mechanism of Action
Clindamycin inhibits bacterial protein synthesis by binding to the 23S RNA of the 50S subunit of the ribosome. Clindamycin is predominantly bacteriostatic.
Although clindamycin phosphate is inactive in vitro, rapid in vivo hydrolysis converts it to active clindamycin.
Resistance
Resistance to clindamycin is most often caused by modification of the target site on the ribosome, usually by chemical modification of RNA bases or by point mutations in RNA or occasionally in proteins. Cross resistance has been demonstrated between lincosamides, macrolides and streptogramins B in some organisms. Cross resistance has been demonstrated between clindamycin and lincomycin.
Antibacterial Activity
Culture and sensitivity testing of bacteria are not routinely performed to establish the diagnosis of bacterial vaginosis (see INDICATIONS AND USAGE); standard methodology for the susceptibility testing of the potential bacterial pathogens, Gardnerella vaginalis, Mobiluncus spp., or Mycoplasma hominis, has not been defined.
The following in vitro data are available but their clinical significance is unknown. Clindamycin is active in vitro against most isolates of the following organisms reported to be associated with bacterial vaginosis:
- •
- Bacteroides spp.
- •
- Gardnerella vaginalis
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- Mobiluncus spp.
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- Mycoplasma hominis
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- Peptostreptococcus spp.
Rx only
This product's labeling may have been updated. For the most recent prescribing information, please visit www.pfizer.com.
LAB-0047-17.0
Revised 02/2026
CLEOCIN® VAGINAL OVULES(CLINDAMYCIN PHOSPHATE VAGINAL SUPPOSITORIES)
Cleocin® Vaginal Ovules (clindamycin phosphate vaginal suppositories)
DIRECTIONS FOR USE
How do I use CLEOCIN Vaginal Ovules?
For vaginal use only. Do not take by mouth.
Use one CLEOCIN Vaginal Ovule daily, preferably at bedtime, for 3 days in a row.
Do not use this product if the foiled pouches containing vaginal ovules are torn, opened, or incompletely sealed.
Read the full directions below before using.
Insertion without the applicator:
- 1.
- Remove the vaginal ovule from its packaging (See Figure 1).
- Figure 1
- 2.
- Holding the ovule with your thumb and a finger, insert it into the vagina (See Figure 2).
Figure 2
- 3.
- Using your finger, gently push the ovule into the vagina as far as it will comfortably go (See Figure 3).
Figure 3
- 4.
- Once inside the vagina, the ovule melts. Lie down as soon as possible. This will keep leakage to a minimum.
- 5.
- Repeat steps 1 through 4, before bedtime, for the next 2 days.
STORAGE CONDITIONS:
Store at 25°C (77°F); excursions permitted to 15 – 30°C (59 – 86°F) [see USP Controlled Room Temperature].
Caution: Avoid heat over 30°C (86°F). Avoid high humidity. See end of carton for the lot number and expiration date.
LAB-0649-4.0
Revised February 2026
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