Some over-the-counter (OTC) and prescription medications can interfere with treatment for hepatitis C or increase the risk of liver damage. Popular vitamins, herbs, and supplements can also lead to complications. Always consult a healthcare professional before use.

Hepatitis C is a liver disease caused by the hepatitis C virus (HCV). HCV infection causes liver inflammation, leading to severe damage and scarring over time.

Your liver works by filtering blood from your gastrointestinal (GI) tract. It also removes toxins from chemicals you might come into contact with and metabolizes medications.

Having a liver disease like hepatitis C increases your risk of damage from taking certain drugs, herbal supplements, and vitamins. This effect is known as chemical-induced liver damage (hepatotoxicity).

Symptoms of hepatotoxicity may include:

  • abdominal pain, especially in the upper right area of your abdomen
  • appetite loss
  • dark-colored urine
  • fatigue
  • fever
  • itchy skin or rash
  • nausea or vomiting
  • unexplained weight loss
  • yellowing of the skin or eyes (jaundice)

If you have acute or chronic hepatitis C, it’s important to share your current list of vitamins, medications, and supplements with your healthcare professional.

They can determine your risk for interactions and recommend potential alternatives.

Your healthcare professional can also offer safety information about drugs and other substances you’d like to add to your overall regimen or use on an as-needed basis.

Acetaminophen (Tylenol) is an OTC pain reliever. You can also find it in certain cold and flu medications.

Despite its wide availability, acetaminophen may put you at risk of liver damage. The risk is greater when you take acetaminophen in large doses all at once or in small doses for an extended period.

These risks apply regardless of whether you have preexisting liver disease. Thus, acetaminophen may not be your best source of pain relief when you have hepatitis C.

That said, there’s a lack of clinical guidelines on the use of acetaminophen for people with hepatitis C. Low, temporary doses may be safe for some people.

But if you have cirrhosis of the liver or drink alcohol regularly, your doctor may recommend that you avoid it.

Some experts recommend testing for hepatotoxicity every 3–6 months in people who have chronic hepatitis C and take acetaminophen regularly.

It’s important to talk with your doctor before use to determine whether this medication could worsen any existing liver damage. If your doctor approves, take no more than 2,000 milligrams (mg) daily for 3–5 consecutive days.

Amoxicillin is an antibiotic commonly used to treat bacterial infections.

Although hepatotoxicity is rare among healthy individuals, having a history of liver disease may increase your chance of drug-induced liver damage.

If you experience an infection that requires an antibiotic, ensure your healthcare professional knows about your hepatitis C diagnosis. They may prescribe another medication to treat your bacterial infection.

NSAIDs are another class of OTC pain relievers, including aspirin (Bayer) and ibuprofen (Advil). NSAIDs are also present in some cold and flu medications.

People who have uncomplicated hepatitis C may be able to tolerate NSAIDs at low doses. However, it’s best to avoid NSAIDs altogether if you have cirrhosis or other severe complications associated with chronic hepatitis C.

Complementary and alternative remedies, including those targeted toward liver health, are rising. But if you have hepatitis C, certain supplements and herbs may cause more harm than good.

One supplement to avoid is iron. Iron overload is already prevalent in many people with hepatitis C and liver disease. Iron is available in most OTC multivitamins to prevent iron deficiency anemia. Unless you have anemia and a healthcare professional instructs otherwise, choose a multivitamin without iron.

Too much vitamin A can also cause hepatotoxicity in people with hepatitis C. Experts recommend limiting your daily intake of vitamin A to less than 5,000 international units per day.

Certain herbs may also be dangerous when you have an HCV infection. St. John’s wort, for example, can interfere with your hepatitis C treatments and make them less effective.

The following herbs may also increase your risk of hepatotoxicity:

  • black cohosh
  • chaparral
  • comfrey
  • distaff thistle
  • germander
  • greater celandine
  • kava
  • red yeast rice extract
  • skullcap
  • Yohimbe

While certain medications and supplements can help improve your health and quality of life, not all substances are safe for people with hepatitis C.

You may be especially vulnerable if you have chronic hepatitis C, severe liver damage, or cirrhosis. Talk with your doctor before trying any new medications or supplements.