Amoxicillin: Side effects, dosage, uses, and more (original) (raw)

Amoxicillin is an antibiotic. It’s used to treat infections caused by certain types of bacteria.
Amoxicillin oral tablet comes as immediate-release (IR) or chewable tablets. The chewable tablet and IR tablet are only available as generic drugs.
Amoxicillin also comes as a capsule and a suspension. All forms are taken by mouth. (This article focuses on the oral tablet forms only.)

Amoxicillin oral tablet does not cause drowsiness, but it can cause other side effects.

More common side effects

The more common side effects of amoxicillin oral tablet can include:

If these side 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 with 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:

Hypersensitivity reactions. Symptoms can include:
- flu-like symptoms, such as fever, body aches, or sore throat
- a painful red or purple rash that spreads
- blisters that could cause the skin to break down and cause open sores
Liver damage. This effect is rare. Symptoms can include:
- increased liver enzymes shown on a blood test
- pain in the abdomen (stomach area)
- yellowing of the skin and eyes
- tiredness
Serious skin reaction.* This side effect is rare. Symptoms may include:
- flu-like symptoms, such as fever, body aches, or sore throat
- a skin rash and discoloration
- swollen lymph nodes
- itchiness

* Serious skin reactions were not reported in clinical trials of amoxicillin. However, they have been reported since the drug was approved.

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 professional who knows your medical history.

Finishing therapy: It’s important to finish the entire course of amoxicillin treatment as prescribed by your doctor. Do not stop taking this drug or skip doses if you start to feel better. This could cause your infection to last longer. You could also develop a resistance to the medication. This means that if you get a bacterial infection in the future, you may not be able to treat it with amoxicillin.
Diarrhea: Amoxicillin may cause diarrhea. Call your doctor if you have bloody or watery diarrhea, with or without stomach cramps and fever.
Serious skin reaction: Skin reactions can occur during amoxicillin treatment. In rare cases, serious skin reactions such as Steven-Johnson syndrome or toxic epidermal necrolysis may occur. Talk with your doctor if you experience a skin rash or condition that becomes bothersome or doesn’t go away.
Serious allergic reaction: This drug can cause a serious allergic reaction. This reaction can be fatal (cause death). If you’re allergic to other antibiotics, such as penicillins or cephalosporins, your risk for an allergic reaction may be higher. Call your doctor right away if you have trouble breathing or swelling of your throat or tongue while you’re taking this drug.

Amoxicillin is a prescription antibiotic. It’s used to treat infections caused by a certain type of bacteria. It may be used as part of combination therapy. This means you may need to take it with other medications.

The oral tablet comes as an immediate-release (IR) tablet and chewable tablet. These are only available as generic drugs.

Generic drugs usually cost less. Amoxicillin also comes as a capsule and a suspension. All forms are taken by mouth. This article focuses on the oral tablet forms only.

Why it’s used

Amoxicillin is an antibiotic. It’s used to treat infections caused by a certain type of bacteria.

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

How it works

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

Amoxicillin works by killing bacteria and stopping its growth in your body.

How long it lasts

The effects of amoxicillin should last as long as you continue taking the drug. Amoxicillin is typically a short-term treatment.

Amoxicillin typically stays in your system for 8 to 12 hours after your most recent dose. It’s possible to continue experiencing some effects of amoxicillin after you stop taking the drug, especially during this 8-hour to 12-hour period. However, the drug’s effects typically end when your treatment ends or soon afterward.

There have been reports of diarrhea lasting for up to 2 months after people stopped amoxicillin treatment. If you experience diarrhea after stopping amoxicillin, especially along with a fever or abdominal pain, talk with your doctor.

Amoxicillin oral tablets start working right away after taking a dose. It can take up to a couple of days after your first dose for the drug to start reducing symptoms of your infection.

If you have questions about how long amoxicillin treatment or its effects last, you can talk with your doctor.

As with all medications, the cost of amoxicillin can vary. The actual price you’ll pay depends on your insurance plan, your location, and the pharmacy you use. You can refer to this article for details about the cost of amoxicillin treatment.

Financial and insurance assistance

Financial assistance to help you pay for amoxicillin may be available.

Medicine Assistance Tool and NeedyMeds are two websites offering resources that may help decrease the price you pay for amoxicillin. They also offer tools to help you find low cost healthcare, as well as educational resources. To learn more, visit their sites.

You can also refer to the coupons in this article for possible ways to save on amoxicillin oral tablets.

To learn more about saving money on prescriptions, check out this article.

Mail-order pharmacies

Amoxicillin may be available through a mail-order pharmacy. Using this service may help lower the drug’s cost and allow you to get your medication without leaving home.

If you’re interested in this option, check with your doctor, pharmacist, or insurance company. Some Medicare plans may help cover the cost of mail-order medications.

If you don’t have insurance, you can ask your doctor or pharmacist about online pharmacy options.

This dosage information is for amoxicillin oral tablet. 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

Forms and strengths

Generic: amoxicillin

Form: oral tablet
Strengths: 500 milligrams (mg), 875 mg
Form: oral chewable tablet
Strengths: 125 mg, 250 mg

Note: Amoxicillin also comes as a capsule and a suspension, both of which are taken by mouth. This article focuses on the oral tablet forms only.

Dosage for infections of the ears, nose, and throat

IMMEDIATE-RELEASE TABLET AND CHEWABLE TABLET

Adult dosage (ages 18–64 years)

Typical dosage is 500 mg every 12 hours, or 250 mg every 8 hours.

Child dosage (ages 3 months–17 years)

Typical dosage is 25 mg per kilogram per day (mg/kg/day) in divided doses every 12 hours, or 20 mg/kg/day in divided doses every 8 hours.

The children’s dosage listed here is meant for children who weigh less than 88 pounds (40 kg). Children who weigh more than 88 pounds should be dosed according to the adult recommendations.

Child dosage (ages 0–2 months)

Maximum dosage is 30 mg/kg/day. Your child’s doctor can tell you more about dosage.

Dosage for urinary tract infections

Adult dosage (ages 18–64 years)

Typical dosage is 500 mg every 12 hours, or 250 mg every 8 hours.

Child dosage (ages 3 months–17 years)

Typical dosage is 25 mg/kg/day in divided doses every 12 hours, or 20 mg/kg/day in divided doses every 8 hours.

Child dosage (ages 0–2 months)

Maximum dosage is 30 mg/kg/day. Your child’s doctor can tell you more about dosage.

Older adult 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, more 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 lower dose or a different dosing schedule. This can help keep levels of this drug from building up too much in your body.

Special considerations

For children’s dosage: The children’s dosage listed here is meant for children who weigh less than 88 pounds (40 kg). Children who weigh more than 88 pounds should be dosed according to the adult recommendations.

Dosage for skin infections

Adult dosage (ages 18–64 years)

Typical dosage is 500 mg every 12 hours, or 250 mg every 8 hours.

Child dosage (ages 3 months–17 years)

Typical dosage is 25 mg/kg/day in divided doses every 12 hours, or 20 mg/kg/day in divided doses every 8 hours.

The dosage listed here is meant for children who weigh less than 88 pounds (40 kg). Children who weigh more than 88 pounds should be dosed according to the adult recommendations.

Child dosage (ages 0–2 months)

Maximum dosage is 30 mg/kg/day. Your child’s doctor can tell you more about dosage.

Older adult dosage (ages 65 years and older)

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

Dosage for lower respiratory tract infections

Adult dosage (ages 18–64 years)

Typical dosage is 875 mg every 12 hours, or 500 mg every 8 hours.

Child dosage (ages 3 months–17 years)

Typical dosage is 45 mg/kg/day in divided doses every 12 hours, or 40 mg/kg/day in divided doses every 8 hours.

Child dosage (ages 0–2 months)

Maximum dosage is 30 mg/kg/day. This is meant for children who weigh less than 88 pounds (40 kg). Children who weigh more than 88 pounds should be dosed according to the adult recommendations. Your child’s doctor can tell you more about dosage.

Older adult dosage (ages 65 years and older)

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

Dosage for gonorrhea

Adult dosage (ages 18–64 years)

Typical dosage is 3 grams (g) as a single dose.

Child dosage (ages 24 months–17 years)

Typical dosage is 50 mg/kg amoxicillin combined with 25 mg/kg probenecid as a single dose. The children’s dosage listed here is meant for children who weigh less than 88 pounds (40 kg).

Children who weigh more than 88 pounds should be dosed according to the adult recommendations.

Child dosage (ages 0–23 months)

This medication should not be used in children younger than 2 years of age for treatment of gonorrhea.

Older adult dosage (ages 65 years and older)

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

Dosage for stomach and intestinal ulcers

Adult dosage (ages 18–64 years)

Typical dosage for triple therapy: 1 g amoxicillin with 500 mg clarithromycin and 30 mg of lansoprazole, all given twice per day for 14 days.
Typical dosage for dual therapy: 1 g amoxicillin and 30 mg of lansoprazole, given three times per day for 14 days.

Child dosage (ages 0–17 years)

This drug has not been studied in children to treat stomach and intestinal ulcers.

Older adult dosage (ages 65 years and older)

Your doctor may start you on a lower dose or a different dosing 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.

Amoxicillin oral tablet 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 with your doctor or pharmacist.

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

Drugs that increase the risk of side effects from amoxicillin

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

Probenecid: Taking probenecid with amoxicillin could lead to increased blood levels of amoxicillin. A doctor may need to decrease the dose of amoxicillin in some patients.
Allopurinol: If you use allopurinol and amoxicillin together, you may develop a rash.

Interactions that increase the risk of side effects from other drugs

Taking amoxicillin with certain medications raises your risk of side effects from these medications. Amoxicillin increases the amount of these drugs in your body.

Examples of these drugs include drugs to treat blood clots. These are called anticoagulants (or blood thinners) and include warfarin (Jantoven), apixaban (Eliquis), heparin, and others.

If you use these drugs with amoxicillin, you have a higher risk of bleeding. Your doctor may adjust your dose of amoxicillin as a result.

Interactions that can make your drugs less effective

When amoxicillin is less effective: When amoxicillin is used with certain drugs, it may not work as well. In vitro studies have shown potential interactions that can cause the amount of amoxicillin in your body may be decreased.

Because in vitro studies are only conducted in a lab and not on live subjects, it is not clear whether this can significantly impact you if you’re taking amoxicillin with these drugs.

Nevertheless, examples of these drugs include:

Chloramphenicol
- If you use these drugs together, your doctor will likely keep your dosage of amoxicillin the same.
Macrolides, such as erythromycin, clarithromycin, or azithromycin
- If you use these drugs together, your doctor will likely keep your dosage of amoxicillin the same.
Sulfonamides, such as sulfamethoxazole
- If you use these drugs together, your doctor will likely keep your dosage of amoxicillin the same.
Tetracyclines, such as tetracycline or doxycycline
- If you use these drugs together, your doctor will likely keep your dosage of amoxicillin the same.

When other drugs are less effective: When certain drugs are used with amoxicillin, they may not work as well. This is because the amount of these drugs in your body may be decreased. Examples of these drugs include:

Oral contraceptives (birth control)
- If you need to take amoxicillin, you should consider using a barrier method of birth control while on amoxicillin. Or, your doctor may prescribe a different form of birth control for you.

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 professional about possible interactions with all prescription drugs, vitamins, herbs and supplements, and over-the-counter drugs that you’re taking.

This drug comes with several warnings.

Allergies

Amoxicillin can cause a severe allergic reaction. Symptoms can include:

trouble breathing
swelling of your throat or tongue

If you have an allergic reaction, call your doctor or seek guidance from America’s Poison Centers at 800-222-1222 or through its online tool. If your symptoms are severe, 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).

Warnings for people with certain health conditions

For people with mononucleosis (mono or kissing disease): Amoxicillin raises your risk of developing a severe rash.

For people with diabetes: Amoxicillin may cause you to have a false-positive reaction when testing for glucose (sugar) in the urine. Talk with your doctor about how to manage your blood sugar while taking amoxicillin.

For people with kidney disease : If you have severe kidney disease, your kidneys may not clear this drug from your body quickly. As a result, levels of amoxicillin may build up in your body. To help prevent this, your doctor may give you a lower dose of this drug.

Warnings for other groups

For pregnant people: Research in animals has not shown adverse effects on the fetus when pregnant animals were exposed to amoxicillin. There haven’t been enough studies done on humans to be certain if the drug poses a risk to the fetus. However, you may want to still speak with your doctor if you’re pregnant or planning to become pregnant.

For people who are breastfeeding (nursing): Amoxicillin may pass into breast milk and may cause side effects in a child who is breastfed. Talk with your doctor if you are breastfeeding your child. You may need to decide whether to stop breastfeeding or stop taking this medication.

For older adults (ages 65 years and over): The kidneys of older adults may not work as well as those of younger adults. This can cause your body to process drugs more slowly. As a result, more of a drug stays in your body for a longer time. This raises your risk of side effects.

Amoxicillin oral tablet 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: Your bacterial infection may not heal or may get worse.

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.

It’s important to finish the entire course of treatment as prescribed by your doctor. Do not stop taking the drug or skip doses if you start to feel better. This could cause your infection to last longer.

You could also develop a resistance to the medication. This means if you get a bacterial infection in the future, you may not be able to treat it with amoxicillin.

If you take too much: You could have dangerous levels of the drug in your body. Symptoms of an overdose may not be significant at less than 250 mg/kg. In higher-dose cases, it may lead to kidney failure.

If you think you’ve taken too much of this drug, call your doctor or seek guidance from America’s Poison Centers at 800-222-1222 or through its online tool. 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. But 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 of your infection should ease.

Keep these considerations in mind if your doctor prescribes amoxicillin oral tablet for you.

General

Take this drug at the time(s) recommended by your doctor.
You can take the amoxicillin capsule, tablet, or suspension with or without food.
You can crush, cut, or chew regular or chewable amoxicillin tablets.

Storage

Store amoxicillin at room temperature between 59°F and 86°F (15°C and 30°C). Keep this drug away from light. Don’t store this medication in moist or damp areas, such as bathrooms.

Refills

A prescription for this medication may be 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 in a checked bag. Keep it in your carry-on bag.
Don’t worry about airport X-ray machines. They can’t hurt your medication.
You may need to show airport staff the pharmacy label for your medication. Always carry the original prescription-labeled box 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.

Clinical monitoring

You and your doctor should monitor certain health issues. This can help make sure you stay safe while you take this drug. These issues include your:

Kidney function. Blood tests can check how well your kidneys are working. If your kidneys aren’t working well, your doctor may decide to lower your dosage of this drug.
Liver function. Blood tests can check how well your liver is working. If your liver isn’t working well, your doctor may lower your dosage of this drug.

The cost of these blood tests will depend on your insurance coverage.

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

Disclaimer: Medical News Today 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 another 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.