Overview
DESCRIPTION Cefaclor, USP, the active ingredient in cefaclor extended-release tablets USP, is a semisynthetic cephalosporin antibiotic for oral administration. Cefaclor, USP, is chemically designated as 3-chloro-7-D(2-phenylglycinamido)-3-cephem-4-carboxylic acid monohydrate. The cefaclor extended-release tablets formulation of cefaclor differs pharmacokinetically from the immediate-release...
Mechanism of Action
CLINICAL PHARMACOLOGY Pharmacokinetics The cefaclor extended-release tablet formulation of cefaclor is pharmacokinetically different from the cefaclor immediate-release capsule formulation of cefaclor. (See TABLE 1 .) No direct comparisons with the suspension formulation of cefaclor have been conducted; therefore, there are no data with which to compare the pharmacokinetic properties of the extended-release tablet formulation and the suspension formulation. Until further data are available, the pharmacokinetic equivalence of the extended-release tablet and the suspension formulations should NOT be assumed.
Indications
- INDICATIONS AND USAGE To reduce the development of drug-resistant bacteria and maintain the effectiveness of cefaclor extended-release tablets USP and other antibacterial drugs, cefaclor extended-release tablets USP 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.
Common Doses
- 500 mg
- 250 mg
- 1000 mg
- 750 mg
Dosage
DOSAGE AND ADMINISTRATION The absorption of cefaclor extended-release tablets is enhanced when it is administered with food. (See CLINICAL PHARMACOLOGY .) Therefore, cefaclor extended-release tablets should be administered with meals (i.e., at least within one hour of eating) . The extended-release tablets should not be cut, crushed, or chewed. See INDICATIONS AND USAGE for information about patients for whom cefaclor extended-release tablets are indicated.
Contraindications
- CONTRAINDICATIONS Cefaclor extended-release tablets are contraindicated in patients with known hypersensitivity to cefaclor and other cephalosporins.
Side Effects
- ADVERSE REACTIONS Clinical Trials There were 3272 patients treated with multiple doses of cefaclor extended-release tablets in controlled clinical trials and an additional 211 subjects in pharmacology studies. There were no deaths in these trials thought to be related to toxicity from cefaclor extended-release tablets. Treatment was discontinued in 1.7% of patients due to adverse events thought to be possibly or probably drug-related.
Interactions
- Drug Interactions Antacids The extent of absorption of cefaclor extended-release tablets is diminished if magnesium or aluminum hydroxide-containing antacids are taken within 1 hour of administration; H 2 blockers do not alter either the rate or the extent of absorption of cefaclor extended-release tablets. Probenecid The renal excretion of cefaclor is inhibited by probenecid. Warfarin There have been rare reports of increased prothrombin time with or without clinical bleeding in patients receiving cefaclor and warfarin concomitantly.