6 Augmentin Side Effects You Should Know About

If you have a bacterial infection, Augmentin (amoxicillin/clavulanate) is a common antibiotic your healthcare provider may turn to. It treats various infections, ranging from ear and sinus infections to urinary tract infections. It’s in the same family of antibiotics as penicillin (Penicillin VK).

Augmentin is a combination of two medications — amoxicillin and clavulanate — and each one has a specific role. Amoxicillin is the antibiotic that fights unwanted bacteria. Clavulanate is the sidekick. It strengthens amoxicillin by stopping bacteria from breaking it down.

For most people, Augmentin is effective and safe. But, it’s not without its side effects. Coming up is a look at six of the most notable Augmentin side effects and how to deal with them.

1. Diarrhea

Diarrhea is the most common side effect of Augmentin. Nearly 1 in 10 people who take it develop diarrhea. Diarrhea is more common with Augmentin than amoxicillin alone.

Why does Augmentin cause diarrhea? The simple answer: it can do its job too well.

While Augmentin goes to work fighting harmful bacteria, it can do the same to good bacteria that live naturally in your gut. Without these good bacteria, the ability to digest normally may be interrupted. On top of that, the clavulanate part of Augmentin can speed up how quickly your gut moves. This can also lead to diarrhea.

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Diarrhea typically goes away once your Augmentin prescription is finished. There is also some research that suggests certain probiotics can help prevent and manage diarrhea. But if diarrhea is bothersome or overwhelming, you may want to ask your healthcare provider if they can adjust your treatment regimen.

It’s less common, but all antibiotics can raise the risk of Clostridioides difficile (C. diff) diarrhea. This is a type of infectious diarrhea that needs quick medical treatment. Preventing and managing C. diff diarrhea is discussed in another GoodRx Health article.

2. Nausea and vomiting

Many medications can be irritating to the stomach and cause discomfort. Augmentin is no exception. About 3% of people taking Augmentin in initial studies reported nausea. Vomiting was less common.

If you have nausea or vomiting while taking Augmentin, there are some ways to manage your symptoms.

Tips like these may help manage nausea, vomiting, and/or diarrhea:

• Take your medication at the start of a meal or snack.

• Drink plenty of water.

• Avoid spicy or fried foods.

• Consider trying ginger, peppermint, or acupressure treatments.

• Ask your pharmacist about over-the-counter medications for nausea.

Thankfully, these stomach-related side effects don’t usually last for long. They should go away after completing your course of medication.

3. Skin rashes

Skin rashes affected about 3% of people who took Augmentin in initial studies. These rashes may cause small, itchy bumps on your skin. They usually start on the chest or back and spread to the arms and legs. This is not usually related to an allergic reaction.

The risk of skin rashes is higher if you’re actually sick with a virus, not a bacteria. For example, one study found that up to nearly 70% of people sick with mononucleosis (“mono”) may experience a rash if they recently took amoxicillin. The virus appears to make people more sensitive to Augmentin and related antibiotics.

Another skin condition, called Stevens-Johnson syndrome (SJS), is a rare but serious type of rash that’s been reported. It causes the skin to blister and peel. This can lead to serious issues, like skin infection, trouble breathing, and pain in different parts of your body. If Augmentin is causing symptoms of SJS, you should stop taking it and get medical help as soon as you can.

Since skin rashes vary by situation, it’s a good idea to check in with your healthcare provider if you develop one.

4. Liver changes

There have been a number of reports of connecting Augmentin to medication-related liver problems. It can sometimes affect your liver function, but it’s typically not serious.

Liver injury can show up during and after treatment with Augmentin, but you may not see any symptoms. In more advanced cases, you may notice fatigue, a low fever, and abdominal pain. Itchiness and yellowing skin or eyes could follow.

Thankfully, liver changes from Augmentin are usually temporary and reversible. But be sure to let your healthcare provider know right away if you see any of the symptoms described above. They may run tests to keep tabs on your liver health.

What’s more, certain groups of people are more likely to develop liver issues. If you have one or more of these risk factors, your healthcare provider may want to watch you more closely:

• History of liver problems, like hepatitis

• Advanced age

• Male

• Have taken multiple courses of Augmentin in quick succession

• Long-term treatment with Augmentin

5. Yeast infections

Yeast infection, or candidiasis, is another possible side effect of Augmentin. This is a fungal infection that can develop in the vagina and other moist places, such as the mouth and underarms.

Fungi and bacteria live together naturally on and in your body. But antibiotics, which target bacteria, don’t kill fungi. When bacteria in the body die, it leaves room for fungi spread out. This can result in overgrowth and a fungal infection.

Again, this isn’t common. And yeast infections can usually be avoided with good hygiene — like washing often and avoiding wearing wet clothing for long periods of time.

If you do develop symptoms of a yeast infection, your healthcare provider may recommend stopping or changing your antibiotic in order to manage it. Yeast infections are generally very treatable with antifungal medications, like fluconazole (Diflucan).

6. Black hairy tongue

The name sounds scary, but black hairy tongue (BHT) is a harmless side effect that happens to some people who take Augmentin. Affected people may notice that their taste buds appear longer and darker than normal. Bad breath can also appear.

BHT is not a very common side effect, and the reason why it happens is not entirely clear. One theory is that using antibiotics may change the balance of harmless bacteria that grow normally in the mouth.

There is not much you can do about this side effect. But caring for your mouth by brushing your teeth and tongue can help prevent it. It should resolve soon after finishing your Augmentin prescription.

Do Augmentin side effects vary by formulation?

Possibly. Augmentin comes in many strengths with various amounts of the helper molecule clavulanate. Different amounts of clavulanate compared to amoxicillin seem to cause different rates of diarrhea. But it is unclear whether these differences are related to clavulanate alone.

What’s more, some types of Augmentin cause more diarrhea than others. For example, the extended-release (ER) form of the medication could cause diarrhea more often than the immediate-release (IR) version. Augmentin IR tends to be more commonly prescribed.

When should I contact my healthcare provider about Augmentin side effects?

It’s a good idea to speak with your pharmacist or healthcare provider every time you start a new antibiotic. They can offer tips about the best way to take your medication to prevent side effects in the first place. They can also look at your medication list in advance to prevent Augmentin interactions.

It’s equally important to speak to your provider if you experience side effects from Augmentin after you start taking it. While most side effects are mild and go away on their own, more serious ones are also possible. As a precaution, reach out to your provider if you experience any side effects that are bothersome or don’t go away.

What’s more, some people are allergic to penicillin antibiotics. This can include Augmentin. Make sure to tell your healthcare provider about any medication allergies you have to help lower the risk of a serious allergic reaction.

If you’re taking Augmentin and experience symptoms like hives or trouble breathing, get medical help right away.

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Written by:

Nathan Williams, PharmD, RYT

Nathan is a clinical pharmacist, certified yoga instructor, and medical content writer. His clinical practice has spanned several sub-specialties including: emergency medicine, nutrition, and pediatrics.

Edited by:

Joshua Murdock, PharmD, BCBBS

Joshua Murdock, PharmD, BCBBS, is a licensed pharmacist in Arizona, Colorado, and Rhode Island. He has worked in the pharmacy industry for more than 10 years and currently serves as a pharmacy editor for GoodRx.

Reviewed by:

Alyssa Billingsley, PharmD

Alyssa Billingsley, PharmD, is the director of pharmacy content for GoodRx. She has over a decade of experience as a pharmacist and has worked in clinical, academic, and administrative roles.

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