9 Rifampin Side Effects You Should Know About

Rifampin (Rifadin) is an antibiotic that treats tuberculosis and other infections. But what are the most common rifampin side effects? And how long do side effects from rifampin last? 

Below, we’ll review several rifampin side effects you should know about. We’ll also discuss how to manage them and when you should seek medical care. You may need to take rifampin for several months, so it’s helpful to be prepared for any side effects that may appear while you’re taking it.

Rifampin side effects at a glance

Rifampin is known for causing stomach issues. But other side effects are possible, and in rare cases can be serious. Below is a brief overview of the reported rifampin side effects in clinical studies. This isn’t a complete list, as everyone can react to medications differently. Be sure to discuss any side effects that appear with your healthcare team.

Mild side effects:

• Heartburn

• Bloating

• Belching

• Nausea

• Loss of appetite

• Diarrhea

• Flatulence

• Stomach cramps

• Orange body fluids

• Headache

• Fatigue

• Dizziness

• Drowsiness

• Menstrual changes

Rare but serious side effects:

• Confusion

• Trouble concentrating

• Liver damage

• C.diff diarrhea

• Hypersensitivity reactions, such as flu-like syndrome and hives

• Skin reactions

• Blood disorders

Let’s take a closer look at nine possible rifampin side effects.

1. Heartburn and nausea

It’s common for rifampin to cause stomach issues while you’re taking it. This includes heartburn, nausea, and a loss of appetite. You may feel bloated and experience the urge to belch. You may also have a lower appetite than usual. These side effects are more likely with higher doses of rifampin.

It’s recommended you take rifampin with a full glass of water, which may help with these side effects. But you shouldn’t take it with food — it’s best to take rifampin on an empty stomach 1 hour before or 2 hours after a meal. This helps your body absorb the medication better.

Try eating smaller, more frequent meals to help with nausea. It may also help to avoid spicy and fried foods, as they can worsen nausea and heartburn. If symptoms remain bothersome, talk to your healthcare team about over-the-counter (OTC) treatment options. Just be aware that you shouldn’t take an antacid within an hour of your rifampin dose.

Nausea can also be a sign of liver damage, a more serious rifampin side effect. So be sure to let your medical team know if these symptoms worsen or feel severe.

2. Diarrhea

You may also experience stomach cramps and diarrhea when taking rifampin. These side effects are usually mild, but persistent diarrhea can cause dehydration from fluid loss. So be sure to stay hydrated if you develop this side effect. Avoiding high-fiber foods and sticking to a bland diet may also help.

If diarrhea doesn’t improve on its own, your prescriber may suggest an OTC medication such as loperamide (Imodium A-D).

Good to know: In rare cases, rifampin can cause a serious form of diarrhea known as Clostridioides difficile colitis. If you have severe diarrhea along with a fever, severe stomach pain, and fatigue, contact your prescriber or seek medical care right away. This type of infection can be life threatening if left untreated.

3. Orange teeth and body fluids

Rifampin can make your urine, tears, and sweat a brownish-red or orange color. This can also affect your saliva. While it can be alarming, the color change isn’t serious. But it can be challenging to deal with. Your body fluids should return to a normal color once you stop taking rifampin. But you may want to choose dark-colored clothing to avoid orange sweat stains.

Good to know: The orange color in your tears can also stain contact lenses. You may want to avoid wearing them or switch to daily disposable lenses while you’re taking rifampin. 

Rifampin can also change the color of your teeth. And unlike body fluids, this change may be permanent. If you’re worried about tooth discoloration, contact your medical care team. You may still need to continue taking rifampin. But there may be management options they can recommend.

4. Changes in your period

It’s possible that rifampin may interfere with your normal menstrual cycle while you’re taking it. You may notice abnormal bleeding or a change in the amount of time between periods.

Since rifampin can make periods less predictable, wearing a pantyliner or keeping a pad or tampon on hand can prevent you from being caught off guard. 

If your periods stop altogether or bleeding is severe, be sure to let your medical care team know. There could be another cause. 

Good to know: Rifampin can interfere with hormonal birth control. Not only can this cause menstrual changes, it can make birth control less effective. So it’s best to use a backup birth-control method while you’re taking rifampin if you’re taking hormonal birth control to prevent pregnancy.

5. Drowsiness or confusion

Mental changes aren’t common, but they happen to some people taking rifampin. They can include confusion and trouble concentrating. You may also feel dizzy or more sleepy than usual. In rare cases, you may experience body numbness and have trouble with coordination and movement.

Use caution before driving or doing other activities that require alertness — especially when you first start taking rifampin. It’s also a good idea to move slowly and hold on to something for support to prevent falls.

These side effects may go away on their own with time. But if they persist or worsen, let your prescriber know. They may want to change your rifampin dose or make sure there’s not another cause for your symptoms.

6. Liver damage

Liver damage is a rare rifampin side effect, but it’s a serious one. It’s more likely at high doses or if you have a history of liver problems. Alcohol can also worsen this side effect, so it’s recommended that you avoid alcohol while you’re taking rifampin.

Your prescriber will likely keep an eye on your liver function every few weeks while you’re taking rifampin. But be sure to let them know if you have symptoms of liver problems, such as intense nausea, dark-colored urine, or a yellowing of your eyes and skin (jaundice). They may need to lower your dose or have you stop taking rifampin.

7. Flu-like symptoms

Flu-like symptoms are also possible with rifampin. This can be a rare type of hypersensitivity reaction to rifampin — not a flu infection. Symptoms may include fever, chills, and headache. In rare cases, rifampin can cause damage to your lungs. If this happens you may have trouble breathing, a cough, and chest pain along with flu-like symptoms.

Let your prescriber know if any of these symptoms appear while you’re taking rifampin. In milder cases, they may just suggest staying hydrated, resting, and trying OTC medications for fever and muscle aches. But if you have flu-like symptoms along with trouble breathing, a skin rash, or dizziness, seek medical care right away. There could be something more serious going on that needs prompt attention.

Good to know: These symptoms may be more likely if you don’t take rifampin as prescribed. Stopping and starting rifampin isn’t recommended, and may leave your infection untreated. If you’re having trouble taking rifampin as directed, let your prescriber know.

8. Severe skin reactions

Serious skin reactions are another rare but serious side effect of rifampin. These can include Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS). 

You may notice flushed skin or a red, itchy rash. But more serious symptoms, such as blisters, mouth sores, and peeling skin can also happen. Often, you’ll have a fever and flu-like symptoms before these rashes appear. Swollen lymphs nodes are also possible.

Skin rashes from rifampin can be life threatening if they’re not treated right away. So be sure to let your healthcare team know if you notice any type of skin rash while you’re taking rifampin. This is recommended even if the rash feels mild. But if your rash is severe or you also have an unexplained fever,flu-like symptoms, or swollen lymph nodes, seek medical care right away.

9. Blood disorders

In rare cases, rifampin can cause certain blood disorders. It can lower the levels of different types of blood cells, such as white blood cells, red blood cells, and platelets. This can lead to an increased risk of infection and bleeding. It can also cause a form of anemia that makes you feel dizzy and weaker than usual.

Rifampin may also lower vitamin K levels, which can make bleeding more likely.

Your prescriber may check your blood count from time to time while you’re taking rifampin to watch for these side effects. But let them know if you notice minor bleeding when you brush your teeth or you’re bruising easier than usual. If you start feeling run down or have a fever or other signs of an infection, make them aware of that, too.

More serious bleeding, such as blood in your urine or stool, requires emergency care. You should also seek urgent medical treatment if you have a fever along with trouble breathing or chest pain.

When should you seek medical care for rifampin side effects?

You should report any bothersome side effects to your healthcare team. They can suggest ways to manage them or make a change to your rifampin dose. It also helps alert your prescriber to any early signs of a more serious side effect. Keep in mind that even if side effects are troubling you, you should keep taking rifampin unless your prescriber tells you to stop.

It’s best to seek emergency care if you have blood in your urine or stool, severe diarrhea, or jaundice. A severe skin rash and trouble breathing are also symptoms that indicate emergency care is your best course of action.

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Written by:

Alex Evans, PharmD, MBA

Alex Evans, PharmD, MBA, has been a pharmacist for 12 years. His first job was floating in a community chain pharmacy.

Edited by:

Stacia Woodcock, PharmD

Stacia Woodcock, PharmD, is a pharmacy editor for GoodRx. She earned her Doctor of Pharmacy degree from the University of Kentucky and is licensed in New York and Massachusetts.

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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