Generic Name: Cefaclor

  • What is Cefaclor?

    Cefaclor is a cephalosporin antibiotic used to treat ear, nose, throat, respiratory tract, urinary tract, and skin infections caused by specific bacteria. Ceclor CD, an extended-release form of the drug, is also used for bronchitis.

  • What is the most important information I should know about Cefaclor?

    If you are allergic to either penicillin or cephalosporin antibiotics in any form, consult your doctor before taking Cefaclor. There is a possibility that you are allergic to both types of medication. If a reaction occurs, it could be extremely severe. If you take the drug and feel signs of an allergic reaction, seek medical attention immediately.

    Diarrhea is a common problem caused by antibiotics, which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, people can develop watery and bloody stools (with or without stomach cramps and fever), even as late as ≥2 months after having taken the last dose of the antibiotic. If this occurs, contact your doctor as soon as possible.

  • Who should not take Cefaclor?

    Do not use Cefaclor if you are sensitive to or have ever had an allergic reaction to it or any other cephalosporin antibiotic.

    Do not take this medication if you have a history of gastrointestinal problems, particularly bowel inflammation (colitis).

  • What should I tell my doctor before I take the first dose of Cefaclor?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Cefaclor. Also, talk to your doctor about your complete medical history, especially if you have had bowel inflammation or other stomach disease.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.


    Adults: The usual dose is 250 milligrams (mg) every 8 hours. For more severe infections, such as pneumonia, your doctor may increase the dosage.

    Children: The usual daily dosage is 20 mg per 2.2 pounds of body weight, divided into smaller doses and taken every 8 or 12 hours. In more serious infections, such as middle ear infection, the usual daily dose is 40 mg per 2.2 pounds of body weight divided into smaller doses. The total daily dose should not exceed 1 gram.

    Ceclor CD

    The usual dose is 500 mg every 12 hours for 7 days.

    Sore Throat, Tonsillitis, and Skin Infections
    The usual dose is 375 mg every 12 hours for 10 days (sore throat and tonsillitis) or 7-10 days (skin infections).

    Children: The safety and effectiveness of Ceclor CD in children <16 years old have not been established.

  • How should I take Cefaclor?

    Your doctor will only prescribe Cefaclor to treat a bacterial infection. It will not cure a viral infection, such as the common cold. It is important to follow the full dosage schedule of Cefaclor, even if you are feeling better in a few days. Not completing the full dosage schedule may decrease the drug's effectiveness and increase the chances that the bacteria may become resistant to Cefaclor and similar antibiotics.

    Cefaclor works fastest when taken on an empty stomach. You may take it with food to avoid stomach upset.

    Ceclor CD should be taken with meals or at least within 1 hour of eating. Do not cut, crush, or chew the tablets.

  • What should I avoid while taking Cefaclor?

    Do not stop taking Cefaclor even if you are feeling better. Doing so may lead to new infections that are more difficult to treat.

  • What are possible food and drug interactions associated with Cefaclor?

    If Cefaclor is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Cefaclor with antacids containing aluminum or magnesium (which interact with Ceclor CD only), probenecid, or warfarin.

  • What are the possible side effects of Cefaclor?

    Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.

    Side effects of Cefaclor may include: diarrhea, hives, itching, fever, abdominal pain

    Side effects of Ceclor CD may include: diarrhea, headache, nasal inflammation, nausea

  • Can I receive Cefaclor if I am pregnant or breastfeeding?

    The effects of Cefaclor during pregnancy and breastfeeding are unknown. Talk with your doctor before taking this drug if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What should I do if I miss a dose of Cefaclor?

    Take it as soon as you remember. If it is almost time for your next dose, skip the one you missed and go back to your regular schedule. Never take two doses at the same time.

  • How should I store Cefaclor?

    Store at room temperature in a tightly closed container. Refrigerate Cefaclor suspension and discard any unused liquid after 14 days.

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