cefaclor (Raniclor)

What is cefaclor, and how does it work (mechanism of action)?

Cefaclor is a semi-synthetic (partially man-made) oral antibiotic in the cephalosporin family of antibiotics. The cephalosporin family includes cephalexin (Keflex), cefuroxime (Zinacef), cefpodoxime (Vantin), cefixime (Suprax), cefprozil (Cefzil) as well as many injectable antibiotics. Like other cephalosporins, cefaclor stops bacteria from multiplying by preventing bacteria from forming the walls that surround them. The walls are necessary to protect bacteria from their environment and to keep the contents of the bacterial cell together. Bacteria cannot survive without a cell wall. Cefaclor is effective against many different bacterial organisms such as Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, E. coli, and many others.

Is cefaclor available as a generic drug?


Do I need a prescription for cefaclor?


What are the uses for cefaclor?

Cefaclor is a cephalosporin antibiotic prescribed for staph, E. coli, middle ear, and urinary tract infections, and for tonsilitis, bronchitis, and laryngitis.

What are the side effects of cefaclor?

Cefaclor is generally well tolerated, and side effects usually are transient. Reported side effects include:

Cefaclor should be avoided by patients with known allergy to cephalosporin type antibiotics. Since cefaclor is chemically related to penicillin, patients allergic to penicillin can have an allergic reaction (sometimes even anaphylaxis) if given cefaclor. Treatment with cefaclor and other antibiotics can alter the normal bacteria flora of the colon and permit overgrowth of C. difficile, a bacteria responsible for pseudomembranous colitis. Patients who develop pseudomembranous colitis as a result of antibiotics treatment can experience diarrhea, abdominal pain, fever, and sometimes even shock.


Bowel regularity means a bowel movement every day. See Answer

What is the dosage for cefaclor?

The usual adult dose of cefaclor is 250-500 mg every 8 hours or 375-500 mg every 12 hours.

Which drugs or supplements interact with cefaclor?

Aluminum or magnesium containing antacids reduce the absorption of cefaclor from the intestine. Separating the administration of cefaclor and such antacids by one hour prevents this interaction.

Is cefaclor safe to take if I'm pregnant or breastfeeding?

There are no adequate studies of cefaclor in pregnant women.

Small amounts of cefaclor are secreted in breast milk. The effects of this small amount on the infant is unknown.

What else should I know about cefaclor?

What preparations of cefaclor are available?

Tablets (chewable): 125, 187, 250, and 375 mg. Capsules: 250 and 500 mg. Oral Suspension: 125, 187, 250, and 375 mg/5ml.

How should I keep cefaclor stored?

Capsules should be stored at room temperature, 59 F - 86 F (15 C - 30 C) in a tightly closed container. The oral suspension should be stored in the refrigerator in a tightly closed container.


Cefaclor (Raniclor) is an antibiotic in the cephalosporin family. It is prescribed for staph, e. coli, tonsilitis, bronchitis, laryngitis, middle ear, and urinary tract infections. Side effects, warnings and precautions, drug interactions, and safety information should be reviewed prior to taking any medication.

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