Clindamycin Phosphate - Clindamycin Phosphate gel prescribing information
INDICATIONS AND USAGE
Clindamycin phosphate gel is indicated in the treatment of acne vulgaris. In view of the potential for diarrhea, bloody diarrhea and pseudomembranous colitis, the physician should consider whether other agents are more appropriate (see CONTRAINDICATIONS , WARNINGS and ADVERSE REACTIONS ).
DOSAGE AND ADMINISTRATION
Apply a thin film of clindamycin phosphate gel twice daily to affected area.
Keep containers tightly closed.
CONTRAINDICATIONS
Clindamycin phosphate gel is contraindicated in individuals with a history of hypersensitivity to preparations containing clindamycin or lincomycin, a history of regional enteritis or ulcerative colitis or a history of antibiotic-associated colitis.
ADVERSE REACTIONS
In 18 clinical studies of various formulations of clindamycin phosphate using placebo vehicle and/or active comparator drugs as controls, patients experienced a number of treatment emergent adverse dermatologic events [see table below].
| Number of Patients Reporting Events | |||
| Treatment Emergent Adverse Event | Solution n=553(%) | Gel n=148(%) | Lotion n=160(%) |
| Burning | 62 (11) | 15 (10) | 17 (11) |
| Itching | 36 (7) | 15 (10) | 17 (11) |
| Burning/Itching | 60 (11) | # (–) | # (–) |
| Dryness | 105 (19) | 34 (23) | 29 (18) |
| Erythema | 86 (16) | 10 (7) | 22 (14) |
| Oiliness/Oily Skin | 8 (1) | 26 (18) | 12 • (10) |
| Peeling | 61 (11) | # (–) | 11 (7) |
# not recorded
• of 126 subjects
Orally and parenterally administered clindamycin has been associated with severe colitis which may end fatally.
Cases of diarrhea, bloody diarrhea and colitis (including pseudomembranous colitis) have been reported as adverse reactions in patients treated with oral and parenteral formulations of clindamycin and rarely with topical clindamycin (see WARNINGS ).
Abdominal pain, gastrointestinal disturbances, gram-negative folliculitis, eye pain and contact dermatitis have also been reported in association with the use of topical formulations of clindamycin.
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.
DESCRIPTION
Clindamycin phosphate gel, USP contains clindamycin phosphate, USP, at a concentration equivalent to 10 mg clindamycin per gram.
Clindamycin phosphate is a water soluble ester of the semi-synthetic antibiotic produced by a 7(S)-chloro-substitution of the 7(R)-hydroxyl group of the parent antibiotic lincomycin.
The gel contains following inactive ingredient: allantoin, carbopol, methyl paraben, polyethylene glycol, propylene glycol, purified water and sodium hydroxide.
The structural formula is represented below:
The chemical name for clindamycin phosphate is Methyl-7-chloro-6,7,8-trideoxy-6-(1 methyl- trans -4-propyl-L-2-pyrrolidinecarboxamido)-1-thio-L- threo -α-D- galacto- octopyranoside 2-(dihydrogen phosphate).
CLINICAL PHARMACOLOGY
Mechanism of Action
The mechanism of action of clindamycin in treating acne vulgaris is unknown.
Pharmacokinetics
Following multiple topical applications of clindamycin phosphate at a concentration equivalent to 10 mg clindamycin per mL in an isopropyl alcohol and water solution, very low levels of clindamycin are present in the serum (0 ng/mL to 3 ng/mL) and less than 0.2% of the dose is recovered in urine as clindamycin.
Although clindamycin phosphate is inactive in vitro , rapid in vivo hydrolysis converts this compound to the antibacterially active clindamycin.
Microbiology
Clindamycin inhibits bacterial protein synthesis by binding to the 23S RNA of the 50S subunit of the ribosome. Clindamycin is bacteriostatic.
Antimicrobial Activity
Clindamycin is active in vitro against most isolates of Propionibacterium acnes; however, the clinical significance is unknown.
Resistance
Resistance to clindamycin is most often caused by modification of specific bases of the 23S ribosomal RNA. Cross-resistance between clindamycin and lincomycin is complete. Because the binding sites for these antibacterial drugs overlap, cross resistance is sometimes observed among lincosamides, macrolides and streptogramin B. Macrolide-inducible resistance to clindamycin occurs in some isolates of macrolide-resistant bacteria.
HOW SUPPLIED
Clindamycin phosphate gel USP, 1% containing clindamycin phosphate equivalent to 10 mg clindamycin per gram are a transparent gel free from lumps and foreign matter without any separation and is supplied as follows:
NDC 72578-118-01 in tube of 30 g
NDC 72578-118-02 in tube of 60 g
Store at 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C to 30°C (59°F to 86°F) [See USP Controlled Room Temperature].
Protect from freezing.
Call your doctor for medical advice about side effects. You may report side effects to Viona Pharmaceuticals Inc. at 1-888-304-5011 or FDA at 1-800-FDA-1088.
For more information, go to Viona Pharmaceuticals Inc. at 1-888-304-5011.
Mechanism of Action
The mechanism of action of clindamycin in treating acne vulgaris is unknown.
