Highlights for cefaclor

  1. Cefaclor oral capsule is only available as a generic drug.
  2. Cefaclor comes as a capsule, extended-release tablet, and suspension you take by mouth.
  3. Cefaclor oral capsule is used to treat bacterial infections. These include infections of the ear, skin, lungs and respiratory tract, throat, tonsils, and urinary tract.
  • Allergic reactions warning: In rare cases, this drug may cause an allergic reaction. Tell your doctor if you have any signs of an allergic reaction. These can include a severe skin rash, skin blisters or peeling, trouble breathing, or swelling of your face, throat, arms, or legs.
  • Stomach problems warning: This drug can increase your risk of stomach and intestine problems. These include colitis and infection with a type of bacteria called Clostridium difficile. Both of these issues can range from mild to life-threatening. Tell your doctor right away if you have diarrhea during treatment with this drug.
  • Medication usage warning: You may start feeling better before you finish taking all of your medication, but you should keep taking your medication as prescribed until it’s gone. If you stop taking your medication, your infection may not be treated and the bacteria may become resistant to the drug. This means that cefaclor or other antibiotics won’t work for you to treat future infections caused by these bacteria.

Cefaclor is a prescription drug. It comes as a capsule, extended-release tablet, and suspension you take by mouth.

Cefaclor oral capsule is only available as a generic drug. Generic drugs usually cost less than brand-name drugs.

This drug may be used as part of a combination therapy. This means you may need to take it with other medications.

Why it’s used

Cefaclor oral capsule is used to treat bacterial infections. These include infections of the ear, skin, lungs and respiratory tract, throat, tonsils, and urinary tract.

How it works

Cefaclor belongs to a class of drugs called cephalosporin antibiotics. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.

Cefaclor works by stopping the growth of the bacteria causing your infection. This causes your infection to go away.

Cefaclor oral capsule doesn’t cause drowsiness, but it can cause other side effects.

More common side effects

The more common side effects that can occur with cefaclor include:

If these effects are mild, they may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.

Serious side effects

Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:

  • Stomach problems such as Clostridium difficile and colitis. Symptoms can include:
    • severe diarrhea
    • stomach pain
    • nausea
    • vomiting
  • Severe allergic reaction. Symptoms can include:
    • trouble breathing
    • swelling of your throat and tongue
    • itchiness
    • hives
    • severe skin problems, such as a rash or peeling

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this information includes all possible side effects. This information is not a substitute for medical advice. Always discuss possible side effects with a healthcare provider who knows your medical history.

Cefaclor oral capsule can interact with other medications, vitamins, or herbs you may be taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well.

To help avoid interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking. To find out how this drug might interact with something else you’re taking, talk to your doctor or pharmacist.

Examples of drugs that can cause interactions with cefaclor are listed below.

Increased side effects from other drugs

Taking cefaclor with certain medications raises your risk of side effects from those drugs. Examples include:

  • Blood thinners such as warfarin. Taking these drugs together may increase your risk of bleeding.

Increased side effects from cefaclor

Taking cefaclor with certain medications raises your risk of side effects from cefaclor. This is because the amount of cefaclor in your body may be increased. Examples of these drugs include:

  • Probenecid. Taking these drugs together may increase your risk of stomach problems.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs interact differently in each person, we cannot guarantee that this information includes all possible interactions. This information is not a substitute for medical advice. Always speak with your healthcare provider about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you are taking.

This drug comes with several warnings.

Allergy warning

Cefaclor can cause a severe allergic reaction. If you’ve had an allergic reaction to penicillin antibiotics, you may be at a higher risk of allergic reaction to cefaclor. You should not take this drug if you’ve had an allergic reaction to other cephalosporin antibiotics.

Symptoms of an allergic reaction can include:

  • trouble breathing
  • swelling of your throat, tongue, face, arms, or legs
  • itching
  • hives
  • severe skin problems, such as rash or peeling

If you develop these symptoms, call 911 or go to the nearest emergency room.

Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal (cause death).

Alcohol interaction warning

Drinking alcohol may slow down your recovery from the infection while you take this drug. You shouldn’t drink alcohol during treatment with this medication. Talk to your doctor if this may be a problem.

Warnings for people with certain health conditions

For people with stomach or intestinal problems: This drug increases the risk of stomach or intestinal problems, including colitis. Ask your doctor if this drug is safe for you.

Warnings for other groups

For pregnant women: Cefaclor is a category B pregnancy drug. That means two things:

  1. Research in animals has not shown a risk to the fetus when the mother takes the drug.
  2. There aren’t enough studies done in humans to show if the drug poses a risk to the fetus.

Talk to your doctor if you’re pregnant or planning to become pregnant. Animal studies do not always predict the way humans would respond. Therefore, this drug should only be used in pregnancy if clearly needed.

For women who are breastfeeding: Cefaclor may pass into breast milk and cause side effects in a child who is breastfed. Talk to your doctor if you breastfeed your child. You may need to decide whether to stop breastfeeding or stop taking this medication.

For seniors: The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

For children: The capsule form has not been studied in infants younger than 1 month. Capsules should not be used in people younger than 1 month.

All possible dosages and drug forms may not be included here. Your dosage, drug form, and how often you take the drug will depend on:

  • your age
  • the condition being treated
  • how severe your condition is
  • other medical conditions you have
  • how you react to the first dose

The dosage information below is for the conditions that this drug is most often prescribed to treat. This list may not contain all conditions that your doctor can prescribe this drug for. If you have questions about your prescription, talk with your doctor.

Drug forms and strengths

Generic: Cefaclor

  • Form: oral capsule
  • Strengths: 250 mg, 500 mg

Dosage for ear infection

Adult dosage (ages 18 years and older)

  • The typical dosage is 250 mg three times per day, or every 8 hours.
  • For more severe infections, your doctor may double your dosage to 500 mg three times per day.

Child dosage (ages 1 month to 17 years)

  • The typical dosage is 40 mg/kg per day.
  • The maximum dosage is 1 g per day.

Child dosage (younger than one month)

This medication has not been studied in infants younger than 1 month of age. It should not be used in people younger than 1 month of age.

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Dosage for lower respiratory tract infection or pneumonia

Adult dosage (ages 18 years and older)

  • The typical dosage is 250 mg three times per day, or every 8 hours.
  • For more severe infections (such as pneumonia), your doctor may double your dosage to 500 mg three times per day, every 8 hours.

Child dosage (ages 1 month to 17 years)

  • The typical dosage is 20 mg/kg of body weight per day in divided doses three times per day, or every 8 hours.
  • For serious infections or infections caused by resistant bacteria, typical dosage is 40 mg/kg per day, with a maximum dosage of 1 g per day.

Child dosage (younger than one month)

This medication has not been studied in infants younger than 1 month of age. It should not be used in people younger than 1 month of age

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Dosage for pharyngitis

Adult dosage (ages 18 years and older)

  • The typical dosage is 250 mg three times per day, or every 8 hours.
  • For more severe infections, your doctor may double your dosage to 500 mg three times per day.

Child dosage (ages 1 month to 17 years)

  • The typical dosage is 20 mg/kg of body weight per day in divided doses three times per day, or every 8 hours.
  • For serious infections or infections caused by resistant bacteria (bacteria that can’t be treated with certain antibiotics), the typical dosage is 40 mg/kg per day, with a maximum dosage of 1 g per day.

Child dosage (younger than one month)

This medication has not been studied in infants younger than 1 month of age. It should not be used in people younger than 1 month of age

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Dosage for tonsillitis

Adult dosage (ages 18 years and older)

  • The typical dosage is 250 mg three times per day, or every 8 hours.
  • For more severe infections, your doctor may double your dosage to 500 mg, three times per day.

Child dosage (ages 1 month to 17 years)

  • The typical dosage is 20 mg/kg of body weight per day in divided doses three times per day, or every 8 hours.
  • For serious infections or infections caused by resistant bacteria, the typical dosage is 40 mg/kg per day, with a maximum dosage of 1 g per day.

Child dosage (younger than one month)

This medication has not been studied in infants younger than 1 month of age. It should not be used in people younger than 1 month of age.

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Dosage for urinary tract infection

Adult dosage (ages 18 years and older)

  • The typical dosage is 250 mg three times per day, or every 8 hours.
  • For more severe infections, your doctor may double your dosage to 500 mg, three times per day.

Child dosage (ages 1 month to 17 years)

  • The typical dosage is 20 mg/kg of body weight per day in divided doses three times per day, or every 8 hours.
  • For serious infections or infections caused by resistant bacteria, the typical dosage is 40 mg/kg per day, with a maximum dosage of 1 g per day.

Child dosage (younger than one month)

This medication has not been studied in infants younger than 1 month of age. It should not be used in people younger than 1 month of age.

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Dosage for skin or skin structure infection

Adult dosage (ages 18 years and older)

  • The typical dosage is 250 mg three times per day, or every 8 hours.
  • For more severe infections, your doctor may double your dosage to 500 mg, three times per day.

Child dosage (ages 1 month to 17 years)

  • The typical dosage is 20 mg/kg of body weight per day in divided doses three times per day, or every 8 hours.
  • For serious infections or infections caused by resistant bacteria, the typical dosage is 40 mg/kg per day, with a maximum dosage of 1 g per day.

Child dosage (younger than one month)

This medication has not been studied in infants younger than 1 month of age. It should not be used in people younger than 1 month of age.

Senior dosage (ages 65 years and older)

The kidneys of older adults may not work as well as they used to. This can cause your body to process drugs more slowly. As a result, a higher amount of a drug stays in your body for a longer time. This raises your risk of side effects.

Your doctor may start you on a lowered dosage or a different treatment schedule. This can help keep levels of this drug from building up too much in your body.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always speak with your doctor or pharmacist about dosages that are right for you.

When to call the doctor

  1. If you finish your treatment and still have symptoms, call your doctor. You may need a higher dosage or a different medication to treat your infection.
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Cefaclor oral capsule is used for short-term treatment. It comes with serious risks if you don’t take it as prescribed.

If you stop taking the drug suddenly or don’t take it at all: If you stop taking this drug suddenly, your infection may not be treated. This could cause the bacteria to become resistant to the drug. That means that cefaclor or other antibiotics won’t work for you to treat future infections caused by these bacteria.

If you don’t take this drug at all, your symptoms and your infection likely won’t get better.

If you miss doses or don’t take the drug on schedule: Your medication may not work as well or may stop working completely. For this drug to work well, a certain amount needs to be in your body at all times. This may also cause your infection to become resistant to the drug.

If you take too much: You could have dangerous levels of the drug in your body. Symptoms of an overdose of this drug can include:

  • nausea
  • vomiting
  • stomach pain
  • diarrhea

If you think you’ve taken too much of this drug, call your doctor or local poison control center. If your symptoms are severe, call 911 or go to the nearest emergency room right away.

What to do if you miss a dose: Take your dose as soon as you remember. If you remember just a few hours before your next scheduled dose, take only one dose. Never try to catch up by taking two doses at once. This could result in dangerous side effects.

How to tell if the drug is working: The symptoms caused by your infection should get better.

Keep these considerations in mind if your doctor prescribes cefaclor for you.

General

  • You can take this drug with or without food.
  • Take this drug at the time(s) recommended by your doctor.
  • You can open the capsule. If you open it, mix its contents with a liquid or applesauce and then take the mixture right away.

Storage

  • Store the capsule at room temperature between 68°F and 77°F (20°C and 25°C).
  • Store this drug away from light.
  • Don’t store this medication in moist or damp areas, such as bathrooms.

Refills

A prescription for this medication is refillable. You should not need a new prescription for this medication to be refilled. Your doctor will write the number of refills authorized on your prescription.

Travel

When traveling with your medication:

  • Always carry your medication with you. When flying, never put it into a checked bag. Keep it in your carry-on bag.
  • Don’t worry about airport X-ray machines. They can’t harm your medication.
  • You may need to show airport staff the pharmacy label for your medication. Always carry the original prescription-labeled container with you.
  • Don’t put this medication in your car’s glove compartment or leave it in the car. Be sure to avoid doing this when the weather is very hot or very cold.

There are other drugs available to treat your condition. Some may be better suited for you than others. Talk to your doctor about other drug options that may work for you.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.