Which antibiotic is not good for the liver? A guide to hepatotoxicity

October 7, 2025 •

3 min read

According to the National Institutes of Health (NIH), antibiotics are the most common cause of drug-induced liver injury (DILI), accounting for 45% of cases. This can cause concern for many patients, prompting the question: which antibiotic is not good for the liver? The answer is not a single drug, but rather a class of medications that carry varying levels of risk for hepatotoxicity.

Quick Summary

Many antibiotics carry a risk of liver injury, with some classes more commonly implicated. Understanding these risks, symptoms, and patient-specific factors is crucial for safe medication use. The severity and pattern of antibiotic-induced liver damage vary widely among different drugs and individuals.

Key Points

Most Common Culprit: Amoxicillin-clavulanate (Augmentin) is the most frequently cited antibiotic causing drug-induced liver injury (DILI).
Hypersensitivity Reaction: Sulfonamide antibiotics can cause liver damage as part of a hypersensitivity reaction, which may include rash, fever, and facial swelling.
Chronic Use Risk: Long-term use of nitrofurantoin for urinary tract infections can lead to chronic liver damage or autoimmune-like hepatitis.
Antitubercular Concerns: Antibiotics used for tuberculosis, such as isoniazid, pose a significant risk of hepatotoxicity, especially when used in combination.
Variable Risk Factors: Individual risk factors for antibiotic-induced DILI include older age, female sex, pre-existing liver disease, alcohol use, and genetic predisposition.
Symptoms to Watch: Pay attention to signs like jaundice, dark urine, severe fatigue, nausea, vomiting, and abdominal pain, which may signal liver distress.

Understanding Drug-Induced Liver Injury (DILI)

Drug-induced liver injury (DILI) occurs when the liver is damaged by medication. As the liver metabolizes drugs, some can cause injury, classified as either intrinsic (dose-dependent, predictable) or idiosyncratic (unpredictable, less common). Antibiotic-induced liver injury is typically idiosyncratic.

Intrinsic DILI: Predictable and dose-dependent, like acetaminophen overdose.
Idiosyncratic DILI: Unpredictable, not dose-related, often linked to immune response or metabolism.

Leading Antibiotic Culprits in Liver Injury

While most antibiotics are safe, some have a higher risk of causing liver damage, although DILI is generally rare and often resolves after stopping the drug.

Amoxicillin-Clavulanate (Augmentin)

This combination is the most frequent cause of antibiotic-induced liver injury in the U.S. and Europe. The clavulanate component is mainly responsible, causing cholestatic injury that affects bile flow.

Onset: Symptoms can appear days or weeks after treatment ends.
Risk Factors: Increased risk in older men (over 65) and with longer or repeated use.

Macrolide Antibiotics

Macrolides such as erythromycin, clarithromycin, and azithromycin have been associated with rare acute liver injury. Erythromycin esters are particularly linked to cholestatic hepatitis, while azithromycin carries an increased mortality risk in patients with existing cirrhosis.

Antitubercular Drugs

Medications for tuberculosis, including isoniazid (INH), rifampin, and pyrazinamide, are known for hepatotoxicity, often used in combination. INH can cause inflammation and necrosis, with higher risk in older patients and alcohol consumers.

Sulfonamide Antibiotics

Sulfa drugs like sulfamethoxazole-trimethoprim can cause idiosyncratic liver injury, sometimes with hypersensitivity symptoms like rash and fever.

Fluoroquinolones

Antibiotics like ciprofloxacin and moxifloxacin can, in rare cases, cause both hepatocellular and cholestatic hepatitis.

Nitrofurantoin

Used for UTIs, nitrofurantoin can cause acute or, rarely with prolonged use, chronic autoimmune-like hepatitis.

Comparison of Hepatotoxic Antibiotics


Antibiotic Class	Examples	Typical Liver Injury Pattern	Common Risk Factors
Penicillin Combinations	Amoxicillin-Clavulanate (Augmentin)	Cholestatic or Mixed	Older age, male sex, repeat courses
Macrolides	Erythromycin, Azithromycin	Cholestatic or Hepatocellular	Pre-existing liver disease
Sulfonamides	Trimethoprim-Sulfamethoxazole	Mixed (Hypersensitivity)	HIV positive status, older age
Fluoroquinolones	Ciprofloxacin, Moxifloxacin	Hepatocellular or Cholestatic	Pre-existing liver disease
Antitubercular Drugs	Isoniazid, Rifampin	Hepatocellular	Alcohol use, older age
Tetracyclines	Tetracycline, Minocycline	Steatosis, Autoimmune (Minocycline)	High IV doses, pregnancy (Tetracycline)

Signs and Symptoms of Liver Damage

Be aware of potential liver injury signs while taking antibiotics. Symptoms vary and may appear during or after treatment.

Jaundice: Yellowing of skin or eyes.
Nausea, Vomiting, Fatigue: Flu-like symptoms.
Abdominal Pain: Discomfort in the upper right abdomen.
Dark Urine/Light Stools: Changes indicating liver issues.
Itching: Severe itching without rash.
Fever/Rash: Possible hypersensitivity signs.

How to Reduce the Risk of Antibiotic-Induced Liver Damage

Patients can take steps to minimize risk and ensure prompt action.

Inform Your Doctor: Share any history of liver disease.
Follow Dosage: Adhere to prescribed dosage and duration.
Limit Alcohol: Excessive alcohol can increase risk with certain medications.
Monitor Symptoms: Watch for any changes and contact your doctor immediately if you notice signs of liver injury.

Conclusion

While antibiotics are crucial for bacterial infections, some carry a risk of liver damage, particularly amoxicillin-clavulanate, macrolides, sulfonamides, and antitubercular drugs. Risk is low for most but higher for those with existing liver conditions, older age, or certain genetic factors. Safe antibiotic use requires open communication with your doctor, following instructions, and watching for signs of liver distress. The benefits of treatment usually outweigh the low risk, but a personalized assessment is best. For more information, consult the LiverTox website.

Frequently Asked Questions

The combination antibiotic amoxicillin-clavulanate (brand name Augmentin) is the most commonly reported cause of drug-induced liver injury from antibiotics in many large case series. The damage is linked to the clavulanate component.

No, most antibiotics are safe for the liver. The risk of developing drug-induced liver injury (DILI) from antibiotics is low, and most cases are idiosyncratic, meaning they are unpredictable and occur only in a small number of people.

In most cases, antibiotic-induced liver injury is reversible and liver function returns to normal after the medication is discontinued. However, in rare instances, severe or prolonged injury can lead to chronic liver problems or, in very severe cases, liver failure.

The onset of liver injury can vary widely. For some antibiotics, like amoxicillin-clavulanate, symptoms can appear weeks after the treatment course is completed. For others, such as those that cause hypersensitivity reactions, symptoms might appear sooner.

For patients with elevated liver enzymes, antibiotics that are primarily cleared by the kidneys rather than metabolized by the liver are often considered safer. These include many third-generation cephalosporins, such as ceftriaxone, and certain fluoroquinolones, like ciprofloxacin and levofloxacin.

Early signs of liver damage can include feeling unwell, fatigue, nausea, and abdominal pain. As the condition progresses, more specific signs like jaundice (yellowing of the skin and eyes), dark urine, and itching may appear.

No, but they should exercise greater caution. Patients with pre-existing liver disease, such as cirrhosis, should inform their doctor, who will select an antibiotic with a lower hepatotoxic risk and carefully monitor liver function throughout treatment.