Liver Toxic Drugs: Types and Complications

Drug-induced liver injury is the most common cause of sudden liver failure in the United States and Europe. Liver toxicity is dose-dependent, meaning that higher doses are more likely to cause damage.

Some drugs are only known to cause liver damage at very high doses, whereas some can cause damage even at recommended dosages.

Drugs can cause three patterns of liver damage:

• Cholestatic: Injury results from the destruction of bile ducts and accumulation of bile. It tends to mimic bile duct obstruction or gallstones.
• Hepatocellular: Injury results from damage to cells called hepatocytes and causes symptoms similar to viral hepatitis. Hepatocytes make up 70% to 85% of your liver volume and perform most of your liver’s functions.
• Hepatocellular-cholestatic: Liver damage has features of both cholestatic and hepatocellular injury.

Most liver damage caused by medication is minor and temporary, but some people can develop serious liver diseases such as cirrhosis or liver failure. Liver failure can be life threatening and may need to be treated with a liver transplant.

People with drug-induced hepatocellular injury are 2 to 3 times more likely to need a liver transplant than people with cholestatic injury.

Many types of drugs can cause liver damage. In a 2016 study published in the International Journal of Molecular Sciences, researchers found at least one report of liver toxicity in 53% of drugs in the National Institutes of Health’s LiverTox database.

In North America and Europe, the most common cause of toxic hepatitis is acetaminophen (Tylenol). Acetaminophen is harmless at low doses but can cause life threatening liver damage in high amounts.

Liver toxicity from acetaminophen usually occurs in suicide attempts at doses higher than 7.5 grams, and most often over 15 grams.

The researchers also found that more than 100 cases of liver injury were reported in the following medications:

• Antimicrobial drugs:
  • interferon alpha/Peginterferon
• Antibiotics:
  • sulfamethoxazole/Trimethoprim
• Antifungal drugs:
• Antiepileptic drugs:
• Antineoplastic:
• Antituberculosis drugs:
• NSAIDs:
• Immunosuppressive agents:
• Arrhythmia medications:
• Antihypertensive medications:
• Lipid-lowering agents:
• Bodybuilding drugs:
• Gout prophylaxis:
• Chemotherapy:
• Other drugs:
  • chlorpromazine (phenothiazine antipsychotics)
  • dantrolene (muscle relaxant)
  • interferon beta (multiple sclerosis)
  • ticlopidine (platelet inhibitor)
  • propylthiouracil (antithyroid)

Herbal supplements

Many people assume that herbal supplements are safe if they’re marketed as natural. However, many of these supplements can cause liver damage. Some herbal supplements linked to liver damage include:

Symptoms of liver toxicity are similar to other liver diseases. They can include:

Weakness and fatigue are prominent symptoms of hepatocellular injury. Jaundice and itching are typical symptoms of cholestatic injury.

It’s important to stop taking the medication as soon as possible after you develop symptoms.

According to research, you may be at an increased risk for developing drug-induced liver toxicity if you:

• are an older adult
• are born female
• are of African American descent
• consume a high level of alcohol over a long period of time, while using some types of drugs
• have certain genes

There’s debate about whether people with preexisting liver disease develop drug-induced liver illness more frequently. It has been found that they have a higher death rate.

There are no specific tests to diagnose drug-induced liver toxicity. To make a diagnosis, your doctor will consider your medical history and any drugs you’re taking. They’ll likely recommend blood tests to look for signs of liver damage and rule out other conditions. These tests often include:

Treatment for liver injury

In most cases, the only specific treatment needed is to stop taking the medication. High doses of acetaminophen need to be treated in the emergency room.

If you have severe symptoms of liver damage, it’s important to avoid:

• heavy exercise
• alcohol
• acetaminophen
• other substances that harm the liver

You can reduce your chance of developing liver injury by closely following your doctor’s instructions for prescription medications and following the medication instructions for over-the-counter drugs. Your risk of developing toxicity increases at higher medication dosages.

Other things you can do include:

• talking with your doctor before you start taking herbal or dietary supplements
• telling your doctor about all the medications and supplements you’re currently taking
• closely reading the warnings and instruction information that comes with your medication
• reducing the use of nonessential medications
• visiting your doctor for regular checkups
• going to all your scheduled follow-ups

Many types of medications can cause liver injury. The most common cause of drug-induced liver injury in the United States is acetaminophen, usually at doses over 7.5 grams.

Common initial symptoms of drug-induced liver injury include jaundice, fatigue, and weakness. It’s important to contact your doctor right away if you develop signs of liver injury after starting a new medication. Usually, with mild cases, stopping the medication is the only treatment that’s necessary.